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Analyzing environmental and structural characteristics of concrete for carbon mitigation and climate adaptation in urban areas

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Title:
Analyzing environmental and structural characteristics of concrete for carbon mitigation and climate adaptation in urban areas a case study in Rajkot, India
Creator:
Solis, Andrea Valdez ( author )
Place of Publication:
Denver, Colo.
Publisher:
University of Colorado Denver
Publication Date:
Language:
English
Physical Description:
1 online resource (296 pages) : ill. ;

Thesis/Dissertation Information

Degree:
Doctorate ( Doctor of Philosophy)
Degree Grantor:
University of Colorado Denver
Degree Divisions:
Department of Civil Engineering, CU Denver
Degree Disciplines:
Civil Engineering
Committee Chair:
Durham, Stephan A.
Committee Co-Chair:
Ramaswami, Anu
Committee Members:
Corotis, Ross
Xi, Yunping

Subjects

Subjects / Keywords:
Concrete -- Additives ( lcsh )
Carbon dioxide mitigation -- India -- Rajkot ( lcsh )
Climate change mitigation -- India -- Rajkot ( lcsh )
Carbon dioxide mitigation ( fast )
Climate change mitigation ( fast )
Concrete -- Additives ( fast )
Rajkot (India) ( lcsh )
India -- Rajkot ( fast )
Genre:
bibliography ( marcgt )
theses ( marcgt )
non-fiction ( marcgt )

Notes

Review:
Increasing temperatures, varying rain events accompanied with flooding or droughts coupled with increasing water demands, and decreasing air quality are just some examples of stresses that urban systems face with the onset of climate change and rapid urbanization. Literature suggests that greenhouse gases are a leading cause of climate change and are of a result of anthropogenic activities such as infrastructure development. Infrastructure development is heavily dependent on the production of concrete. Yet, concrete can contribute up to 7% of total CO29 emissions globally from cement manufacturing alone. The goal of this dissertation was to evaluate current concrete technologies that could contribute to carbon mitigation and climate adaptation in cities. The objectives used to reach the goal of the study included (1) applying a material flow and life cycle analysis (MFA-LCA) to determine the environmental impacts of pervious and high volume fly ash (HVFA) concrete compared to ordinary portland cement (OPC) concrete in a developing country; (2) performing a comparative assessment of pervious concrete mixture designs for structural and environmental benefits across the U.S. and India; and (3) Determining structural and durability benefits from HVFA concrete mixtures when subjected to extreme hot weather conditions (a likely element of climate change). The study revealed that cities have a choice in reducing emissions, improving stormwater issues, and developing infrastructure that can sustain higher temperatures. Pervious and HVFA concrete mixtures reduce emissions by 21% and 47%, respectively, compared to OPC mixtures. A pervious concrete demonstration in Rajkot, India showed improvements in water quality (i.e. lower levels of nitrogen by as much as 68% from initial readings), and a reduction in material costs by 25% . HVFA and OPC concrete mixtures maintained compressive strengths above a design strength of 27.6 MPa (4000 psi), achieved low to moderate permeability's (1000 to 4000 coulombs), and prevented changes in length that could be detrimental to the performance of the concrete in long-term temperatures above 37.8oC (100oF).
Thesis:
Thesis (Ph.D.)--University of Colorado Denver. Civil engineering
Bibliography:
Includes bibliographic references.
System Details:
System requirements: Adobe Reader.
General Note:
Department of Civil Engineering

Record Information

Source Institution:
|University of Colorado Denver
Holding Location:
|Auraria Library
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
868229870 ( OCLC )
ocn868229870

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Full Text
ANALYZING ENVIRONMENTAL AND STRUCTURAL CHARACTERSITICS OF
CONCRETE FOR CARBON MITIGATION AND CLIMATE ADAPTATION IN
URBAN AREAS: A CASE STUDY IN RAJKOT, INDIA
by
Andrea Valdez Solis
B.S.New Mexico State University2006
M.S. New Mexico State University2008
A dissertation submitted to the
Faculty of the Graduate School of the
University of Colorado in partial fulfillment
of the requirements for the degree of
Doctor of Philosophy
Civil Engineering
2013


2013
ANDREA VALDEZ SOLIS
ALL RIGHTS RESERVED


This dissertation for the Doctor of Philosophy degree by
Andrea Valdez Solis
has been approved for the
Civil Engineering Program
by
Stephan A. Durham, Chair
Anu Ramaswami, Co-Advisor
Amnprakash Kamnanithi
Ross Corotis
Yunping Xi
December 17, 2012
li


Solis, Andrea, Valdez (Ph.D., Civil Engineering)
Analyzing Environmental and Structural Characteristics of Concrete for Carbon
Mitigation and Climate Adaptation in Urban Areas: A Case Study in Rajkot, India
Dissertation directed by Associate Professor Stephan A. Durham
ABSTRACT
Increasing temperatures, varying rain events accompanied with flooding or
droughts coupled with increasing water demands, and decreasing air quality are just some
examples of stresses that urban systems face with the onset of climate change and rapid
urbanization. Literature suggests that greenhouse gases are a leading cause of climate
change and are of a result of anthropogenic activities such as infrastructure development.
Infrastructure development is heavily dependent on the production of concrete. Yet
concrete can contribute up to 7% of total C2 emissions globally from cement
manufacturing alone.
The goal of this dissertation was to evaluate current concrete technologies that
could contribute to carbon mitigation and climate adaptation in cities. The objectives
used to reach the goal of the study included (1)applying a material flow and life cycle
analysis (MFA-LCA) to determine the environmental impacts of pervious and high
volume fly ash (HVFA) concrete compared to ordinary portland cement (OPC) concrete
in a developing country; (2) performing a comparative assessment of pervious concrete
mixture designs for structural and environmental benefits across the U.S. and India; and
(3) Determining structural and durability benefits from HVFA concrete mixtures when
subjected to extreme hot weather conditions (a likely element of climate change).


The study revealed that cities have a choice in reducing emissions, improving
stormwater issuesand developing infrastructure that can sustain higher temperatures.
Pervious and HVFA concrete mixtures reduce emissions by 21% and 47%, respectively,
compared to OPC mixtures. A pervious concrete demonstration in Rajkot, India showed
improvements in water quality (i.e. lower levels of nitrogen by as much as 68% from
initial readings), and a reduction in material costs by 25% HVFA and OPC concrete
mixtures maintained compressive strengths above a design strength of 27.6 MPa (4000
psi)achieved low to moderate permeabilitys (1000 to 4000 coulombs)and prevented
changes in length that could be detrimental to the performance of the concrete in long-
term temperatures above 37.8C (100F).
The form and content of this abstract are approved. I recommend its publication.
Approved: Stephan A. Durham
IV


DEDICATION
I dedicate this work to my parents Loretta Valdez and Andrew Chavez and to all
the people from the pueblitos of Northern New Mexico. The love, care, and support
these people show help others strive for the best, believe, and remain positive in life.


ACKNOWLEDGEMENTS
I would like to thank my advisors Dr. Stephan Durham and Dr. Anu Ramaswami.
My advisors provided me a unique PhD experience that has taught me how to be a
stronger person both in life and in my profession. The PhD was challenging but, Dr.
Duhram and Dr. ramswami helped me to realize the importance of remaining patient,
motivated, and grateful while doing research. I am honored to have studied under the
guidance of these two very important people who are admired for their personalities and
contributions to engineering and sustainability. I come away with a PhD striving to
model the best attributes of my advisors, Dr. Durham for his practicality, passion for
teaching, and appreciation he shows to others and Dr. Ramswami for her devotion and
dedication she puts into every project, ability to challenge and motivate you with her
words, and the courage they both display in being leaders in research.
I would like to emphasize that the PhD experience was feasible and memorable
because of the opportunity to meet and work with various people. If it wasnt for the
times spent drinking tea, talking to and joking with fellow students and staff, or learning
about cultures and collaborating with people across the world I would have overlooked
how exceptional and distinct each person is in this world. It so important to learn how to
work with different people and appreciate that chance to listen to their ideas, knowledge,
concerns, and joys. I want to thank Tom Thuis, Randy Ray, Dr. Nien-Yin Chang, Dr.
Kevin Rens, Dr. Rajaram, Jose Solis, Adam Kardos, Dr. Loren Cobb, Dr. Angie Hager,
Derek Chan, Dr. Rui, Liu, Devon, Krista Nordback, Brian Volmer for all their help
during my research and dissertation preparation. I thank Laasya Bhagavatula, Emani
Kumar, Ashish Rao Ghorpade of ICLEI-South Asia, Mr. Jayant Lakhlani of Lakhlani
vi


Associates, Mitesh Joshi and his family and Alpana Mitra and her family for making me
feel welcomed in Rajkot, India and giving me the honor of working with all of you while
doing the research in Rajkot. Additionally, I appreciate the feedback and commitment
that my committee members (Dr. Ross CorotisDr. Arunprakash Karunanithiand Dr.
Yunping Xi) showed during defense. I would also like to thank the National Science
Foundations Integrative Graduate Education and Research Traineeship (IGERT Award
No. DGE-0654378) for funding my research.
Lastly, I thank my family, friends, and especially my parents. It is hard to explain
how much I appreciate the qualities of my parents because my parents mean a lot to me
and I want to say the right words. My mom is always forgiving, a great listener, and I
admire her for her ability to manage people and make people feel important. My dad is a
very intelligent man that enjoys the simple things in life (like working side by side with
his children), he gives valuable advice and I admire him for how hard he works. I am
able to achieve any goal because my parents have always been there pushing me along,
keeping me focused, and making me believe I have a purpose.
Vll


TABLE OF CONTENTS
Chapter
1.Introduction......................................................................1
1.1 Concrete and Urban Infrastructure..............................................1
1.1.1 Concrete Use..................................................................1
1.1.2 Concrete Infrastructure Is a Source of GHG Emissions ........................3
1.2 Climate Change in Urban Areas................................................3
1.2.1 Flooding or Drought in Urban Areas...........................................4
1.2.2 Extreme Temperatures in Urban Areas...........................................5
1.3 Concrete Infrastructure for GHG Mitigation and Climate Adaptation..............6
1.3.1 Pervious Concrete Past and Contemporary Research.............................7
1.3.2 High Volume Fly Ash Concrete Research with a Focus on Thermal Properties ....9
1.3.3 Main Goal and Knowledge Gaps.................................................13
1.4 Thesis Objectives.............................................................16
1.5 Organization of Thesis........................................................17
2. Case Study Location: The City of Rajkot India...................................19
2.1 Demographics, Population, and Climate.........................................19
2.2 Rajkot Construction and Concrete Infrastructure ..............................21
2.2.1 Personal Account of Construction ............................................22
2.2.2 Rajkot Concrete Infrastructure..............................................25
2.3 Future GHG Mitigation and Climate Adaptation Goals............................29
2.3.1 Storm water/Rainwater Harvesting.............................................31
2.3.2 HVFA Concrete Road Project..................................................32
viii


2.3.3 Collaboration between UC Denver, ICLEI South Asia
and Rajkot Municipal Corporation ........................................34
3. Carbon Mitigation Through Concrete: An MFA-LCA Approach....................36
3.1 Bottom-line: Cement and Concrete Manufacturing in India and the US........36
3.2 Life Cycle Assessment of Cement and Concrete in India ...................41
3.3 Understanding the Cement Production and Concrete Industry in India ......44
3.3.1 Ready Mixed Concrete Industry in India..................................48
3.3.2 Site Mixed Concrete in India ...........................................49
3.3.3 Indian Concrete Mixture Designs ........................................51
3.4 Cement Manufacturing Process in India.....................................52
3.4.1 Phases of Cement Clinker.................................................54
3.4.2 Kilns ...................................................................55
3.5 Energy Consumption within the Cement Industry.............................56
3.5.1 Energy Scenario in the Indian Cement Industry ..........................57
3.5.2 Methods of Energy Efficiency ............................................58
3.6 Management, Energy Efficiency Ventures,
and Emission Trends for Indian Cement Companies ..........................62
3.6.1 Energy Efficiency and Embodied in Cement Manufacturing in India ........63
3.6.2 Emission Trends in Cement Manufacturing in India........................65
3.7 Materials, Fuels, and Emissions Associated with Cement and Concrete .....70
3.7.1 Cement ..................................................................70
3.7.1.1 Overall Result ........................................................76
3.7.1.2 Company to Company Comparison..........................................77
3.7.1.3 Cementitious Materials ................................................79
IX


3.7.1.4 Energy Intensity .....................................................80
3.7.1.5 C2 Emissions Factor Conclusion......................................81
3.7.2 Quarrying and Mining of Other
Raw Materials (Excluding Limestone)......................................82
3.7.3 Coarse and Fine Aggregate Crushing .....................................82
3.7.4 Tranpsportation of Materials............................................83
3.7.5 On-site Mixed Concrete..................................................84
3.7.6 Summary of Life Cycle Inventories.......................................85
3.8 MFA-LCA of Cement Use in Rajkot..........................................87
3.9 MFA-LCA for Concrete Mixtures in Rajkot .................................88
3.10 Summary ................................................................90
4. Stormwater Solution Demonstration with Pervious Concrete:
Structural and Environmental Tests.........................................91
4.1 Study Design and Laboratory Phase I Testing..............................92
4.1.1 Material Properties.....................................................95
4.1.2 Mixture Design .........................................................97
4.1.3 Test Methods............................................................98
4.1.4 Phase I Laboratory Results ............................................105
4.2 Providing Stormwater Management Solutions in Rajkot, India:
A Pervious Concrete System Demonstration.................................112
4.2.1 Introduction...........................................................112
4.2.2 Materials and Methods..................................................116
4.2.3 Test Methods and Results ..............................................124
4.3 Laboratory Phase II Testing (Cubes Versus Cylinders).....................136
4.3.1 Batching and Curing Phase II Laboratory Samples........................138


4.3.2 Sample Shape Effects on the Compressive Strength of Pervious Concrete ....141
4.3.3 Comparing Compressive Strength Results ...................................145
4.3.4 Discussion of Standard Deviations and Population .........................149
4.3.5 Summary of Percent Porosity ..............................................150
4.3.6 Summary of Hydraulic Conductivity.........................................151
4.4 Summary .....................................................................152
5. High Volume Fly Ash Concrete for Hot Weather Conditions:
Structural and Durability Tests ..............................................155
5.1 Literature Regarding Fly Ash Use in India....................................155
5.1.1 Properties of Fly Ash .....................................................155
5.1.2 Fly Ash Consumption in India...............................................157
5.2 Literature on HVFA Concrete for Hot Weather Conditions.....................159
5.3 Phase I study for HVFA in Hot Weather Conditions: India and U.S. Comparison of
Fly Ash Properties (Fly Ash Used in Rajkot, Gujarat, India and Denver, Colorado,
U.S.).....................................................................164
5.4 Phase II: Properties of HVFA and OPC Concrete When
Subjected to Hot Weather Conditions..........................................172
5.4.1 Aggregate Temperatures.....................................................172
5.4.2 Verifying Temperatures of HVFA and OPC Concrete During Hydration ..........175
5.5 Phase III study for HVFA in Hot Weather Conditions: Laboratory Testing of
Structural and Durability Properties ........................................180
5.5.1 Compressive Strength ......................................................186
5.5.2 Modulus of Elasticity......................................................191
5.5.3 Resistance to Rapid Chloride-Ion Penetration...............................191
5.5.4 Length Change .............................................................198
5.6 Applying a Multiple Linear Regression Model to Determine the Significance of
xi


Testing Variables on HVFA Concrete versus OPC Concrete When Subjected to Hot
Weather Conditions .................................................202
5.6.1 Background on Multiple Linear Regression ..............................202
5.6.2 Application of the Multiple Linear Regression Models ..................203
5.6.3 Revision of Multiple Linear Regression Analysis with Original Data.....211
5.7 Summary of Strength, Permeability, Length Change, and Multiple Linear
Regression...............................................................215
6. Conclusions and Recommendations ..........................................218
6.1 Conclusions..............................................................218
6.1.1 Carbon Mitigation: An MFA-LCA Approach ................................218
6.1.2. Climate Adaptation: Pervious Concrete.................................219
6.1.3 Climate Adaptation: HVFA Concrete......................................220
6.2 Contributions............................................................221
6.3 Recommendations and Future Research......................................222
6.3.1 MFA-LCA Recommendations................................................223
6.3.2 Pervious Concrete Recommendations .....................................223
6.3.3 HVFA Concrete Recommendations .........................................225
6.4 Final Remarks Regarding Sustainability ..................................235
References...................................................................236
Appendix
A............................................................................247
B............................................................................253
C............................................................................255
D............................................................................258
xii


Table
LIST OF TABLES
1.1. Summary of the Benefits of Fly Ash Concrete................................10
3.1 Comparison of Energy Use per Tonne of Cement Between the U.S. Cement Industry
and India5s Grasim Industries ..............................................37
3.2 Summary of Energy Use and Emission Factors from Direct and Indirect C2
Emissions between India and the U.S.........................................39
3.3 World Cement Production 2010...............................................46
3.4 Indian Cement Industry Information ........................................48
3.5 Mixture Proportions for Typical Grades of Concrete (Based on Saturated
Surface Dry Conditions).....................................................51
3.6 Average Energy Use Between India
and U.S. Cement Industry for 2009-2010 .....................................58
3.7 Examples of Non-Hazardous and Hazardous Alternative Fuels..................62
3.8 Example Differences in Calcining Emission Coefficients.....................69
3.9 Fuel and Electricity Raw Data Gathered for Calculation of Cement Emission
Factor .....................................................................71
3.10 Country Specific Emission Factors Used in Calculating a Cement Emission
Factor ....................................................................73
3.11 Density Values for Certain Fuels Used in Indian Cement Manufacturing .....73
3.12 MFA-LCA Data for Purchased Electricity ...................................74
3.13 MFA-LCA Data for Company Generated Electricity from Coal..................74
3.14 MFA-LCA Data for Company Generated Electricity
from LDO/Furnace Oil.......................................................74
3.15 MFA-LCA Data for Company Generated Electricity from Natural Gas...........75
3.16 MFA-LCA Data for Thermal Energy from Coal..................................75
3.17 MFA-LCA Data for Thermal Energy from Light Diesel..........................75
xiii


3.18 MFA-LCA Data for Thermal Energy from Furnace Oil.........................75
3.19 MFA-LCA Data for Thermal Energy from High Speed Diesel Oil...............76
3.20 Cement Production from Major Cement Manufacturing Companies that
Deliver to Rajkot, India..................................................76
3.21 Energy Consumption from Major Cement Manufacturing Companies that
Deliver to Rajkot, India..................................................77
3.22 Emissions from Major Cement Manufacturing Companies that Deliver to
Rajkot, India.............................................................79
3.23 Fly Ash Consumption by Major Cement Companies who Deliver to Rajkot,
India ....................................................................80
3.24 Production and Emissions From Quarry and Mining .........................82
3.25 Emission Factors for Aggregate Crushing..................................83
3.26 Emission Factors and Average Distance Travelled
for Cement Transportation.................................................83
3.27 Emission Factors and Average Distance Travelled
for Transport of Aggregate ...............................................84
3.28 Emission Factors and Average Distance Travelled
for Transport of Fly Ash .................................................84
3.29 Specifications of Concrete Mixer ........................................85
3.30 Summary of Emission Factors Leading Up to Concrete Mixing................86
3.31 Reiner5s (2007) Emission Factor Calculations for Ready Mixed Concrete ...86
3.32 Information Regarding Rajkot Cement Use
and Total Emissions per Year..............................................88
3.33 MFA Data for M35, Pervious and HVFA Concrete Mixtures....................89
3.34 LCA Data and Total Emissions Calculations from an MFA-LCA on Concrete
Mixtures .................................................................89
3.35 Cement Material Content and MFA-LCA Emissions for Certain Concrete
Mixtures .................................................................90
xiv


4.1 Chemical Properties of Cement along with Standard Limits....................96
4.2 Physical Properties of Cement Along with Standard Limits ..................96
4.3 Mixture Proportions for Phase I Laboratory Testing.........................98
4.4 Porosity of Samples from Mixture 1 and Mixture 2 (Reported in Percent)....105
4.5 Average Hydraulic Conductivity for Mixture 1 and 2........................108
4.6a Mixutre 1 Compressive Strength Results....................................109
4.6b Mixture 2 Compressive Strength Results ...................................110
4.7 Mixture Proportions for Rajkot............................................120
4.8 Batch Quantities..........................................................120
4.9 Specific Gravity Values Provided used in the
Pervious Concrete Mixture Design...........................................120
4.10 Results of the Calculated Percentage Voids .............................125
4.11 Hydraulic Conductivity of the Pervious Concrete and System ..............126
4.12 Results of Compressive Strength of Pervious Concrete Samples.............129
4.13 Water Quality Analysis of the Water from a Bore Well and Stream..........131
4.14 Additional Results of Stream Water Quality Tests........................134
4.15 Mixture Proportions for Phase II Laboratory Testing.....................138
4.16 Specific Gravities and Absorption Capacities in Phase II Testing .......139
4.17 Compressive Strength Results for M3......................................145
4.18 Compressive Strength Results for M4......................................146
4.19 Cylinder to Cube Strength Ratio
Based on Average Compressive Strengths ...................................147
5.1 Example of Chemical Composition of Fly Ash from Different Countries
(Malhotra & Mehta2008)....................................................156
5.2 Year 2005 Production and Utilization of Fly Ash in India.................158
xv


5.3 Chemical Analysis for Various Fly Ash Sources between the U.S. and India .165
5.4 Mixture Proportions for HVFA Concrete in Rajkot .........................16b
5.5 Compressive Strength Results for Rajkot HVFA Concrete Samples ...........167
5.6 Mixture Proportions for HVFA Concrete in Denver .........................169
5.7 Fresh Concrete Properties for the HVFA Concrete Batch in Denver..........169
5.8 Compressive Strength Results for U.S. HVFA Concrete Samples..............170
5.9 Average Cylinder to Cube Compressive Strength Ratios for U.S. and Indian
HVFA Concrete Mixtures....................................................171
5.10 Mixture Proportioning for Mixture Designs in Phase Ha Testing of HVFA and
OPC Concrete ............................................................176
5.11 Mixture Proportioning for HVFA and OPC Concrete Mixture Designs in
Extreme Hot Weather Condition Testing ...................................181
5.12 ASTM Standards Used for Fresh and Hardened Concrete Tests...............181
5.13 Material Temperatures Before Mixing (And During Mixing for the Heated
Aggregate Mixtures)......................................................185
5.14 Internal Peak Temperatures During Curing................................185
5.15 Matrix for Multiple Linear Regression Analysis .........................205
5.16 Equations of Fitted Curves from 1st Regression Analysis ................206
5.17 Summary of 1st Regression Analysis .....................................206
5.18 Equations of Fitted Curves from 2nd Regression Analysis ................208
5.19 Summary of Regression Analysis When
Including the TB Interaction Term .......................................208
5.20 A Comparison of Equations or Fitted Curves From 2nd and 3rd Regression
Analysis for Compressive Strength .......................................212
5.21 Comparing Significant Variables, R2, and Standard Deviations for
Compressive Strength ....................................................212
5.22 A Comparison of Equations or Fitted Curves From 2nd and 3rd Regression
xvi


Analysis for Permeability ...................................................213
5.23 Comparing Significant Variables, R2, and Standard Deviations for
Permeability ................................................................213
5.24 A Comparison of Equations or Fitted Curves from 2nd and 3rd Regression
Analysis for Length Change ..................................................214
5.25 Comparing Significant Variables, R2, and Standard Deviations for
Permeability ................................................................214
5.26 Summary of F-Statistic and .P-Value from ANOVA.............................215
6.1 Order of Performing Mixtures ................................................227
6.2 Base Mixture Design..........................................................227
6.3 Phase I Testing Summary for Each Mixture.....................................228
6.4 Phase II Testing Summary for Each Mixture ...................................228
XVII


Figure
LIST OF FIGURES
1.1 Concrete Consumption Forecast Compared Against Population Growth (Mehta and
Monteiro, 2006)..............................................................2
2.1 Location of Rajkot within the state of Gujarat, India (Google Maps).........19
2.2 Paver Blocks (a) Removal from Molds (b) Design on Surface of Blocks.........21
2.3 Materials Stock Piled Directly on Construction Site .......................23
2.4 Large Scale Used for Measuring Aggregate and Cement before Batching........24
2.5 Materials Transferred from Scale into Portable Diesel Powered Mixer........24
2.6 Laborers Placing Concrete..................................................24
2.7 Cement Being Emptied from the Bucket and Pulley Machinery..................25
2.8 Breakup of Landuse within City Limits of Rajkot (Rajkot Municipal Corporation,
2006).......................................................................26
2.9 Small Residential Buildings Near the Edge of City Limits...................26
2.10 Indoor Stadium............................................................27
2.11 Buildings Near the Center of the City.....................................27
2.12 Waste Water Treatment Plant...............................................27
2.13 Construction of Housing ..................................................28
2.14 Construction of a Water Tower.............................................28
2.15 Tube Solar Water Heaters Mounted on the Roofs in Rajkot ...................30
2.16 Rajkot Municipal Corporation Office with Passive Cooling Foyer Design......30
2.17 Recharging Pit or Detention Pond Park Being Cleaned.......................31
2.18 Park Filled with Stormwater After a Rain Event............................32
2.19 HVFA Concrete Road on Saurashtra University Campus (a) Two Wheelers and
Tractor on the Road (b) Close up of the Surface of the Road................33
xviii


2.20 Raiya WWTP Site (a) Placing Concrete (b) Curing Concrete.................33
3.1 Life Cycle Phases and Material Flow for Concrete in Rajkot.................44
3.2 Trend in Cement Production for Four Leading Cement Producing Countries (USGS,
2012; Parikh, Sharma, Kumasr, Vimal, IRADe, 2009)..........................47
3.3 Potential Trend in Per Capita Cement Consumption for Four Leading Cement
Producing Countries (USGS2012; Parikhet al2009; United Nations 2010b)...47
3.4 Steps in cement manufacturing process at Grasim Industries Limited Cement
Company (Grasim Industries Limited, 2008)..................................53
3.5 Phase Diagram for Ordinary Portland Cement (Gani, 1997)...................55
3.6 Cyclone Heat Exchangers and Precalciner (Gani, 1997)......................60
3.7 Indian Cement Emission Factors for 1991-2010..............................67
3.8 Concrete Mixer with Mechanical Hopper.....................................84
4.1 Proposed Pervious Concrete System Site.....................................93
4.2 Pervious Parking Lot Pavement on Auraria Campus in Denver, Colorado.......94
4.3 Details of the Pervious Concrete System for the Parking Lot Installation (Hager,
2009).......................................................................95
4.4 Mixture Consistency (a) Too Dry, (b) Proper Amount of Water, (c) Too Wet (Tennis,
Leming, & Akers, 2004)......................................................99
4.5 Compressive Strength Testing (a) Using Neoprene Pads for Cylinders and (b) Steel
Plates for Cubes...........................................................101
4.6 Hydraulic Testing Apparatus (a) Cylinder with Stopper and Putty (b) Hole Drilled in
Cylinder for Draining Water from the Cylinder into the Pervious Concrete...104
4.7 A Side by Side Comparison of the Pervious Concrete Samples.................10b
4.8 Average Compressive Strengths for Mixture 1 and Mixture 2..................110
4.9 Fracture Paths for Cylinder Pervious Concrete Samples......................Ill
4.10 Fracture Paths for Cube Pervious Concrete Samples........................Ill
4.11 Fracture Occurring Through the Aggregate.................................Ill
xix


4.12 Second Proposed Site for the Pervious Concrete System Placement.........114
4.13 (a) A Perforated Pipe Placed in Barrel(b) Image of Barrel...............118
4.14 Base and Sub-Base Layers a) Coarse Aggregate Layer b) Fine Aggregate Layer ..118
4.15 Cloth Fiber used between Coarse and Fine Aggregate Layers...............118
4.16 Profile of the Pervious Concrete System Placed in the Barrel............119
4.17 Evaluation of Pervious Concrete Consistency.............................121
4.18 Rodding the Layers of Pervious Concrete in the Cube Mold................122
4.19 Compacting the Pervious Concrete in the Cube Molds Using (a) Direction 1 and (b)
Direction 2..............................................................122
4.20 Covering the Pervious Concrete with a Wet Jute Bag......................123
4.21 Removal of Pervious Concrete from Cube Molds (a) Close-Up View (b) All Six
Cubes....................................................................123
4.22 Placing Pervious Concrete Cubes in a Water Bath.........................124
4.23 Placement of the Pervious Concrete Samples in Water Filled Container to Determine
Percentage Voids from Volume of Displaced Water..........................124
4.24 Compressive Strength Test and Fracture Path.............................128
4.25 Visual Observations (a) The Sample after Completion of Compressive Strength Test
(b) Breaking the Sample Further by Hand..................................128
4.26 Before and after Percolation (a) Bore Water Samples (b) Stream Water Samples .130
4.27 Samples Collected for Pathogen and B.O.D. Tests (a) Bore Well Water Samples (b)
Stream Water Samples..................................................130
4.28 Steel Roller for Compaction (a) Side View (b) Front View..............136
4.29 Sieve Analysis (a) Phase II Coarse Aggregate, (b) Rajkot Coarse Aggregate, (c)
Phase II Fine Aggregate, (d) Rajkot Fine Aggregate....................140
4.30 Coarse Aggregate (a) Rajkot (b) Phase II.............................141
4.31 Compressive Strength Fractures for M3 (a) Cubes and (b) Cylinders....144
xx


4.32 Compressive Strength Fractures for M4 (a) Cubes and (b) Cylinders.....144
4.33 Fracture Through Aggregate............................................145
4.34 Average Compressive Strength of Cylinders and Cube Mixes for Pervious Concrete
Designed for 2000 psi (13.8 MPa) Strength..............................146
4.35 Relationship between Cylinder and Cube Average Compressive Strengths...147
4.36 Average Compressive Strength with Standard Deviations for All Batches..148
4.37 Average Compressive Strength with Standard Deviations between Cylinders and
Cubes at 7-day and Final-Day Testing for all Batches...................149
4.38 Summary of Percent Porosity for All Batches...........................151
4.39 Summary of Hydraulic Conductivity for all Batches.....................152
4.40 Summary of Hydraulic Conductivity for all Batches Using Falling Head Criteria.152
5.1(a) Vanakbori Fly Ash, (b) Gandhinagar Fly Ash............................165
5.2 Batches (a) Vanakbori and (b) Gandhinagar...............................167
5.3 Cubes (a) Vanakbori and (b) Gandhinagar.................................167
5.4 Average Compressive Strength Result for Rajkot HVFA Concrete Samples.....168
5.5 U.S. and India HVFA Concrete Average Compressive Strength Results........170
5.6 Summary of Average Compressive Strength Results and Standard Deviations
between the U.S. and Indian Sources of Fly Ash...........................171
5.7 Aggregate (a) Storing and Cooling in a Shed and (b) Stockpiling..........173
5.8 Temperatures of Stock-Piled and Stored/Cooled Aggregate.................175
5.9 Campbell Scientific Datalogger (CR 10X) Used to Record Concrete
Temperatures.............................................................177
5.10 Installing the Thermocouple Into Concrete Sample.......................177
5.11 Internal Curing Temperatures of Ambient Cured Fly Ash and OPC Samples
During Trial1 Testing...................................................178
5.12 Internal Curing Temperatures of Heat Cured HVFA and OPC Samples During
xxi


Trial 2 Testing
179
5.13 Surface of Samples after Heat Curing (a) Fly Ash Mixture (b) OPC Mixture.179
5.14 View of (a) Water Curing Tank (i.e. Ideally Cured) and (b) Hot Weather
Curing Tank................................................................182
5.15 Hot Weather Simulation Tank (a) Boards to Keep Heat in (b) Close-Up of
Aluminum Foil Bubble Insulation............................................183
5.16 Schematic of Hot Weather Simulation Tanks.................................183
5.17 Campbell Scientific (a) Datalogger (CR 5000) and (b) Setup for the Ideal and
Hot Weather Simulation Tanks for Recording Concrete Temperatures...........184
5.18 Early Age Compressive Strength (a) No-Heated Aggregate (b) Heated
Aggregate..................................................................188
5.19 Later Age Compressive Strength (a) No-Heated Aggregate (b) Heated
Aggregate..................................................................189
5.20 Compressive Strength Results (a) No-Heated Aggregate, (b) Heated
Aggregate..................................................................190
5.21 Modulus of Elasticity (a) No-Heated Aggregate Concrete (b) Heated
Aggregate Concrete.........................................................192
5.22 Permeability Testing Setup................................................193
5.23 Average Rapid Chloride Ion Permeability Test Results (a) No-Heated
Aggregate, (b) Heated Aggregate............................................197
5.24 Length Change Apparatus...................................................198
5.25 Length Change for No-Heated Aggregate Samples.............................200
5.26 Length Change for Heated Aggregate Samples................................201
5.27 Effects of the Interaction of T and B on Compressive Strength.............209
5.28 Effects of the Interaction of T and B on Permeability.....................210
5.29 Effects of the Interaction of T and B on Percent Length Change............211
6.1 Sample Schedule for Competing Phase I-II Testing...........................228
XXII


6.2 Example of Finite Element Mesh and a Close-Up of a Single Element Based on
Dimensions of the Length Change Beam Made in Lab........................231
6.3 Difference between Elastic Potential Energy of Water Cured and Heat Cured OPC
Concrete Sample after 90 Days of Curing.................................232
6.4 Schematic of Placement of the Thermocouple in Concrete Cylinder........234
XXlll


1.Introduction
1.1 Concrete and Urban Infrastructure
With more than half of the worlds population living in cities the demand of
having effective and well functioning infrastructure for urban areas grows. Many
governments identify the modernization of urban infrastructure as a crucial step for future
economic growth and competitiveness. Howeverexecuting plans for infrastructure in
any nation is a challenge because it usually involves long term strategies and allocating
large amounts of funding even during times of fiscal strain. During the next forty years
infrastructure is expected to cost approximately $70 trillion worldwide with most
spending priorities occurring in the sectors of power/energy, residential, roads/bridges,
railmininghealthcareand water infrastructure (KPMG International2012; Seimens
GlobeScan, MRC McLean Hazel, 2007).
1.1.1 Concrete Use
Much of the urban built environment is constructed from the material known as
concrete. Concrete is one of the most versatile construction materials next to steel.
Concrete infrastructure has had a historic presence dating back to the rule of the Roman
Empire and possibly originating 2000 years before the Romans during Egyptian times.
Even today the basic ingredients within concrete are rock (coarse aggregate), sand (fine
aggregate), water, and a cement powder (once the powder is mixed with water it acts as a
binder for the rest of the ingredients). A typical concrete mix (portland cement concrete)
usually consists of 15% cement by weight (FHWA, 2012). Cement production for the
world between 2009 and 2010 was approximately 3310 million tonnes (USGS, 2012).
Assuming the cement production is the potential consumption for the world and all


cement is used for concrete products consisting 15% cement (by weight) then concrete
consumption in 2009-2010 was about 22.1 billion tonnes. This estimate exceeds the
forecasted concrete consumption that was presented by Mehta and Monteiro (2006) (See
Figure 1.1). Mehta and Monteiro presented Figure 1.1 based on consumption rates
leading up to the year 2002. Concrete consumption was estimated to peak at 16 billion
tonnes (18 billion tons) or 2 tonnes/person when the population was about 10.4 billion
people. With approximately 6.8 billion people between 2009 and 2010 per capita
concrete consumption was about 3.3 tonnes of concrete/person. Note: At this time it
seems as though no one entity keeps record of world consumption and production of
concrete. Some countries or regions keep record of ready mix concrete use but in
developing countries where concrete mixing occurs on-site this does not seem to be taken
into account.
2000
2025
2050
Year
2075
24
22
20
f
o
c
o
18 f
E
16

o
U
12
2100
Figure 1.1 Concrete Consumption Forecast compared Against Population growth
(Mehta and Monteiro, 2006)
2


1.1.2 Concrete Infrastructure Is a Source of GHG Emissions
Concrete infrastructure comes with an environmental price. Cement production,
alone, can contribute between 5 to 7% of global green house gas emissions (Mehta and
Monteiro, 2006; Crow, 2008). Concrete has a large carbon footprint not just due to
cementbut because it is used in large amounts in urban areas as a construction material.
As cities continue to growdemand for new and maintained infrastructure intensifies
which leads to a continued release of greenhouse gas emissions. Greenhouse gas
emissions have been tied to global warming or where the average weather is subject to
warmer changes (one definition of climate change) through scientifically based
assumptions.
1.2 Climate Change in Urban Areas
Scientific evidence points to urban areas as a major contributor to greenhouse gas
(GHG) forced climate change. Anthropogenic (relating to influence of human activity)
waste heat in the form of heating and cooling buildingstrafficconstructionand industry
coincides with increasing urban heat islands and doubled carbon dioxide emissions.
Climate model projections isolating the response of urban micro-climates to local
(anthropogenic waste heat) and global effects, show that cities will experience an
increase in maximum temperatures and frequency of hot nights. For cities such as Delhi
or Los Angeles, 32 to 41 additional hot nights are a result of a low surface heat capacity,
low soil moisture, high energy gains throughout the day, and rapid release of heat from
the soil (McCarthy, Best, & Betts, 2010).
However, a particular challenge in addressing climate change and (GHG)
emissions is engaging cities to have a personal connection with climate change. Various
3


cities across the world do not see climate change as being an issue, because there are
uncertainties or skepticism regarding the cause and seriousness of climate change;
climate change is believed to be too distant of a problem, or making changes are costly
and undesirable for the current lifestyle, and climate change is not a priority compared to
other issues requiring government action (Lorezoni, Cole, Whitmarsh, 2007). Globally,
city governments are constantly balancing maintenance, design, and financial obligations
to keep urban infrastructure reliable and safe. Howeverclimate change can exacerbate
these common infrastructure issues. In factgrowing research in sustainable
infrastructure and climate action planning has provided evidence that failing to address
the results of climate change and greenhouse gas emissions could lead to risks of
increased water demand, heat island effect, declining air and water quality, new and old
health risks emerging, and increased stresses and deterioration on the operation of urban
and rural infrastructure (The World Bank2008; McCarthyBest& Betts2010
MehrotraNatenzonOmojolaFolorusho, Gilbride& Rosenzweig2009). Recently
urban areas are experiencing the effects of a changing climate. Some examples of
present risks for infrastructurein both developed and developing countriesbased on
current climatic conditions are described in the next few paragraphs. Note: The next few
examples of climate change and current risks make reference to India and the United
States because this dissertation has a focus on India.
1.2.1 Flooding or Drought in Urban Areas
Every year Indian cities experience flooding from seasonal monsoons that result
in damage to urban infrastructure and increased health riskshoweverurban
infrastructure may have a contribution to flooding if inadequate stormwater control
4


mechanisms are not developed or improperly developed. But for cities in arid to semi-
arid regions any type of water is an important commodity to conserve. As will be
explained in a later section this dissertation uses Rajkot, India as a case study for
discussing urban concrete infrastructure opportunities to address carbon mitigation and
climate adaptation. In a city like Rajkot, India the climate is hot and dry but flooding can
occur with just rainfall intensities of 100 mm (4 in) due to nonexistent or few storm water
management strategies and hard basaltic rock underlying the top soil of the terrain. But a
concern other than flooding is the potential for climate change to produce more heat and
lower rainfall. For the year 2012, in the state of GujaratIndia 14 districts and 152
talukas (subdivision of a district) declared a state of drought due to receiving less than the
average rainfall of 33 to 152 cms. Water sustains life in many of desert like regions but
urban stormwater management solutions in countries such as India do not currently take
into account the climate change risks for different regions.
1.2.2 Extreme Temperatures in Urban Areas
As mentioned previously extreme temperatures can become another concern for
urban infrastructure. Road infrastructure is a priority for most countries. Currently more
than 70% of paved roads in India are bitumen, with some major highways being concrete.
However, there is increasing interest in investing in road projects using concrete. The
Indian cement industry proclaims the benefits of concrete in road projects as sound
infrastructure long lasting and can save precious foreign exchange spent on
bitumen (CMA, 2010c). Bitumen for asphalt pavements has to be imported into India
(CII, NRC, Ambuja Cement, 2004). The performance of concrete pavements has been
successful in countries like the U.S. however in 2011 the world experienced one of the


warmest years on record leaving a reminder that climate change can affect the soundest
of infrastructure. Sections of concrete pavement buckled due to trying to expand in
weather that was consecutively above 32.20C (90oF). The Minnesota Department of
Transportation explained to Minnesota Public Radio News that concrete pavements had
little room to expand near congested joints thus causing a lift to occur. In Oklahoma City
a prolonged heat wave (+37.8C [100F]) caused concrete roads to buckle near joints
similar to Minnesota, and the incidents were recorded across the entire state of
Oklahoma. Research on climate change and concrete infrastructure has also shown that
concrete infrastructure will face additional deterioration, carbonation, and chloride
induced corrosion as a result of climate change events and increased greenhouse gas
emissions (Wang, Nguyen, Stewart, Syme, & Leitch, 2010).
Concrete has been identified as having a contribution to greenhouse gas emissions
and also having susceptibility to damage and deterioration from the effects of changes in
the climate. But the unique property of concrete, as stated previously, can be its
versatility and ability to serve various purposes (such as climate adaptation) by adjusting
the mixture design to include other materials aside from the four key ingredients.
Additionally, if these materials can replace the use of cement then green house gas
emissions can be reduced.
1.3 Concrete Infrastructure for GHG Mitigation and Climate Adaptation
If cities can identify an association with climate change then an important next
step can be the assessment of effective and efficient adaptation or mitigation strategies
and policies for urban areas and its infrastructure. Urban areas are complex systems and
the vulnerability of each city depends on geographic, sectoral, and social attributes
6


(Mehrotra et al.2009). Many organizations such as the World BankIntergovernmental
Panel on Climate Change (IPCC), Environmental Protection Agency (EPA), and
International Council for Local Environmental Initiatives (ICLEI) are providing local
governments with resources and ideas that can help urban areas prepare, prevent, or adapt
to the possible effects of climate change. The study in this dissertation commenced with
collaborative work between the University of Colorado Denvers Integrative Graduate
Education and Research Traineeship program on Sustainable Urban Infrastructure and
ICLEI-South Asia to develop sustainability assessments of infrastructure and develop
decision support tools customized to Indian infrastructure (i.e. greenhouse gas (GHG)
inventories that includes the buildingtransportationconstruction material sectors) for
cities in South Asia.
Although cities may not know the exact vulnerabilities that urban areas and
concrete infrastructure face under climate change and GHG emission increases it is
expected that increasing GHG emissions leads to an increased risk of climate change
occurring, and with climate change there is the likelihood that flooding, drought, and
increasing temperatures (along with heat islands in urban areas) will have an influence on
urban areas and infrastructure. This dissertation proposes that two concrete technologies
exist to aid in climate adaptation and carbon mitigation for urban areas; pervious concrete
and high volume fly ash concrete.
1.3.1 Pervious Concrete Past and Contemporary Research
Pervious concrete is known as a permeable, gap-graded, or porous concrete which
allows water to percolate through intended voids in the concrete. A mixture design
usually consists of higher proportions of coarse aggregate compared to conventional
7


concrete, a thin layer of cementitious paste to bond and cover the aggregate, and little to
no fine aggregate. In 1852 the United Kingdom began using the no-fines concrete (a
form of the pervious concrete) as a construction material for buildings (Ghafoori & Dutta
1995). However, today pervious concrete is better known in the U.S. as a best
management practice (BMP) technology because it can serve as a stormwater
management tool that can recharge the groundwater, reduce stormwater rnnoff, reduce
the level of contamination in rnn off, and help lower the heat island effect due to its open
pore structure and its lighter color than asphalt pavements (Tennis et. al2004). Also
these same properties have led it to its description as a sustainable concrete. Research
conducted at the University of Colorado Denver (UCD) revealed these various benefits in
a pervious concrete pavement field installation (Hager, 2009). The successful installation
involved the incorporation of 20% fly ash to offset the use of cement,10% replacement
of sand with crushed glass in the sub-base layer and the test section was monitored for
deterioration, clogging, stormwater quality and reduction of the heat island effect. The
results led to recommendations on design, placement and curing in order to produce
durable pervious concrete pavements with sustainable aspects for urban areas in
Colorado. Hager5 s research is one of many types of research exposing the benefits and
promoting the use of pervious concrete. Between 2006 and 2009 research topics ranged
from lab and field tests on pervious concrete to analyzing the capabilities of pervious
concrete to filter compost effluent resulting from agriculture. The various types of
research regarding pervious concrete can be found in appendix A Tables A. 1(a) through
A. 1(e) which lists the research titles, authors, and objectives. Many of these studies have
8


encouraged that cities use pervious concrete for other applications besides pavements and
are listed below:
Alleys and driveways
Highway shoulders
Sidewalks
Low water crossings
Sub-base for conventional concrete pavements
Patios
Walls
Noise barriers
1.3.2 High Volume Fly Ash Concrete Research with a Focus on Thermal Properties
High volume fly ash (HVFA) concrete has been identified as incorporating more
than 50% of fly ash by mass of total cementitious material into concrete (Malhotra &
Mehta2008). In the 1980s Malhotra began testing HVFA concrete by using Class F and
Class C fly ash. Using higher volumes of fly ash in concrete proved to give concrete
improved mechanical properties and possess benefits such as those listed in Table 1.1
(Giaccio & Malhotra, 1988; Malhotra & Mehta, 2008, American Coal Ash Association
[ACAA], 2003; ACAA, 2002). The benefits of fly ash concrete have been taken beyond
the physical, chemical and economic characteristics such that the use of fly asn is an
indirect solution to green house gas (GHG) emissions and is a means for reducing energy
use from cement manufacturing. In addition, the use of fly ash is associated with
avoiding landfill, and reducing the overconsumption of virgin materials.
9


Table 1.1 Summary of the Benefits of Fly Ash Concrete
Benefits of fly ash concrete
High performance/high ultimate Can compensate for fines not round in
strengths some sands
Improved workability and Lowers water demand
flowability
Reduced bleeding and Reduced concrete shrinkage
segregation
Reduced heat of hydration Reduces wear on delivery and plant equipment
Improved durability through Increased resistance to sulfate attack,
reduced permeability alkali-silica reactivity (ASR), and other forms of deterioration
In one particular study performed at the University of Colorado Denver replacement of
cement with 20% and 40% fly ash in concrete mixes reduced greenhouse gas emissions
by 21% to 36%. The study was also unique in showing how per capita usage of cement,
within the City and County of Denver boundariescontributed to the citys total
greenhouse gas footprint (Reiner2007). Reiners work made it possible for cities like
Denver to understand how the environmental impact of the conventional and fly ash
concrete mixes could be quantified and compared with a combined life cycle assessment
and material flow analysis. Also such information could be used as a tool for making
decisions about the impacts we want future infrastructure to have.
One particular characteristic noted from a literature review on HVFA concrete
was the reason for incorporating it into concrete in the 1930s; fly ash was and has been
used to reduce the heat of hydration in mass concrete (Malhotra and Mehta, 2008). In a
study by Malhotra along with Rivest and Bisaillon (as cited by Malhotra & Mehta, 2008)
several concrete monoliths (some made from HVFA and the others made from 100%
cement) showed a difference in temperature of about 22C (39.6F) with the lowest
10


temperatures occurring in the HVFA concrete monoliths. Cements available today have
such a high reactivity that a high heat of hydration is likely to occur even in structures
with thicknesses less than 50 cm (20 in). Although the properties of modern cement
have improvedcements characteristics can render a structure susceptible to thermal
(excessive temperature differences between the concrete and the surrounding
temperature) and drying shrinkage (contracting of hardened concrete due to loss of
capillary water) cracking. These two types of cracking are especially a problem during
hot weather concreting. Taole A.2, found in Appendix A summarizes just a handful of
past research on fly ash concrete related to hot weather concreting applications or
experimentations.
Hot weather concreting means that precautions must be taken when concrete mixing and
placing is occurring at temperatures above 32i (90oF) or when concrete temperatures
are somewhere between 25 C and 35 C (77F and 95F). Common solutions for hot
weather concreting are the following (PCA2002).
Cool concrete materials before mixing
Schedule concrete placements to limit exposure, thus avoiding pouring during the
hottest part of the day
Use chilled water or ice as part of the mixing water
Use of a Type II moderate heat cement
While curing use sunshades, misting, or fogging to limit moisture loss
Apply moisture-retaining films after screeding
Studies on HVFA concrete have shown that thermal and drying shrinkage cracking are
minimized in the concrete as a result of the properties of the fly ash (Malhotra & Mehta,
11


2008; Ravina, 1981; Mehta, 2002; and Senthil and Santhakumar, 2005). HVFA concrete
lowers internal curing temperatures due to fly ash having a lower reaction compared to
cement. Ravina studied lower percentages of fly ash in concrete, but both Ravina and
Mehta express that hot weather concreting with fly ash decreases water demand during
mixing. Also, high concrete temperatures have been shown to reduce strengths in
concrete, however, both studies by Mehta (2002) and Ravina (1981) proved that fly ash
concrete strengths were typically higher than a reference mixture made with ordinary
Portland cement at later ages when both types of concretes were cured in hot
temperatures. Other research has shown that the long-term performance of fly ash
concrete have led to more durable structures that require less maintenance (ACAA
2002).
Mehta (2002), Senthil and Santhakumar (2005) monitored the internal curing
temperature of fly ash concrete and showed that fly ash can prevent thermal cracking.
The study by Senthil and Santhakumar (2005) is one of the few studies where the mixture
designs involved the use of blended cements from India. In India blended cements can
consist of fly ash and cement or ground blast furnace slag and cement which are blended
during the cement manufacturing process. The percentage of fly ash in the blended
cement study by Senthil and Santhakumar was not specified, however the results revealed
that the heat of hydration could be about 5C (9F) higher for the blended cements when
compared to a general purpose cement and a high-strength cement. The surprisingly high
heat of hydration may have been attributed to the fineness of the grinding, according to
the authors; nevertheless the strengths were comparable to the high-strength cement
mixture. Mehta5 s study emphasized that high volume fly ash concrete (with Class F fly
12


ash) would be most beneficial in keeping temperature increases under 30C (54F) and
under such temperature maintenance thermal cracking was prevented for a foundation
placed under warm and humid conditions. When 50% or more fly ash is utilized, the fly
ash and the cement complement one another, such that some heat is generated from the
presence of cement but part of the heat is concentrated on the acceleration of the
pozzolanic reaction.
Besides possessing beneficial properties for hot weather concreting HVFA
concrete has other thermal properties that could be related to energy efficiency. The
research by Bentz et al.(2010) was unique in the aspect of examining the thermal
benefits of hardened fly ash concrete while the previous authors monitored temperatures
of fresh concrete and then evaluated the mechanical properties after hardening. Although
the mechanical properties were of importance to Bentz et al.the goal of the research was
to evaluate the energy efficiency or insulative potential or high volume fly ash concrete
for use in buildings (residential or commercial). Bentz, et al.did comment that the
aggregates affected the thermal conductivity of the HVFA concrete; however, other
research referenced in Table A.2 did not make reference to aggregate effects. Thus, it
may be beneficial to research the temperature of freshly mixed fly ash concrete as
affected by temperature of aggregate.
1.3.3 Main Goal and Knowledge Gaps
The research regarding climate change and carbon dioxide should not be
overlooked. The literature review and recent events have supported the idea that carbon
is linked to climate change, and urban areas are facing a new challenge that could bring
flooding, drought, and rising and prolonged temperatures. There is no doubt that the
13


climate change and carbon dioxide expose society to environmental and health risks.
But, there is minimal research regarding the effects of carbon dioxide and climate change
on the urban infrastructure that society depends on.
Without proper infrastructure planning and designingthat takes into account
climate change impactsthere is the possibility that new infrastructure could experience
premature deterioration while the deterioration rate of older infrastructure could be
exacerbated. Based on the literature review very few studies exist that explore how
concrete infrastructure will be affected. However, the literature review did highlight the
benefits that pervious concrete and high volume fly ash concrete could contribute towards
climate adaptation. Despite the 80 plus years of research regarding both pervious
concrete and high volume fly ash concrete many city governments are unaware of these
benefits and therefore do not encourage the regular use of these two concrete
technologies (Ghafoori and Dutta, 1995; Solis, Durham, Rens and Ramaswami, 2010).
Studies by Hager (2009) and Reiner (2007) are great examples of how they used
their research to demonstrate and improve on the advantages of pervious concrete and fly
ash concrete. Recall, that the study by Reiner also indicated that fly ash use in concrete
designs can reduce emissions resulting from cement and the manufacturing of concrete.
In another study by Reiner along with Ramaswami, Hillman, Janson, and Thomas (2008),
it was found that just by including the embodied energy of key urban materials such as
concrete, quantification of per capita GHG emissions was improved for the city of
Denver and became the benchmark from which the city could begin developing ways in
reducing their emissions as whole or within certain sectors such as the design of
construction materials.
14


Main Goal of Thesis:
The main goal of the study is to evaluate pervious and HVFA concretes contribution to
carbon mitigation and climate adaptation in cities.
Summary of Knowledge Gaps
However, in order to support these recommendations the following knowledge gaps,
which were identified from the literature review, are studied further and play a major role
in this dissertation.
GHG emissions Reiners study was unique in quantifying the emissions from
ready mix concrete operations in a city (2007). However, for cities that rely on
on-stie mixing operations, such as in developing countries (i.e. India), are
emissions comparable to those of where cities primarily use ready mix
companies?
Pervious Concrete There has been no research regarding the ability to transfer
well-established and research supported pervious concrete designs to other
regions having material differences. Research has indicated that size and shape
of aggregate can change certain properties of the pervious concrete but it is
unclear, if all materials differed (aggregate, water, cement), whether these
changes drastically affect strength, porosity, filtration, and hydraulic
conductivity all at once.
High Volume Fly Ash Concrete It is already known that HVFA concrete is a
well established solution to lowering the heat of hydration and preventer of
thermal and drying shrinkage cracks during hot weather concreting. However,
the literature on climate change has indicated that there is the likelihood of
15


extended periods where temperatures will rise above average temperatures. The
question that research has not quite answered is how does do these prolonged
high temperature events affect materials before mixing? How are fresh concrete
properties affected after mixing when materials have been affected by the hot
weather? Do current hot weather curing methods work for extended periods of
high temperatures? Will hardened properties change dramatically when
temperatures extend past 28 or more days of curing? The main question that has
been left unanswered is whether fly ash has the capabilities of mitigating the
effects of extended periods of heat even when required to cure for 56 to 90 days?
1.4 Thesis Objectives
The collaborative work with ICLEI South Asia and University of Colorado Denver
presented the opportunity to study the knowledge gaps mentioned in the previous section.
Thus the main objectives of this research were the following
This study applied the powerful tool of MFA-LCA to determine the
environmental impacts of pervious and HVFA concrete compared to ordinary
Portland cement (OPC) concrete in a developing country
In this study a comparative assessment of pervious concrete mixture designs for
structural and environmental benefits across the U.S. and India was performed
In this study it was necessary to determine whether there are structural and
durability benefits from HVFA in concrete mixtures when subjected to extreme
hot weather conditions
16


1.5 Organization of Thesis
1) In Chapter 2 the case study is introduced. The city of Rajkot, India is described
through climatecement consumptionstormwater managementand current construction
with and without fly ash concrete. The citys current interest in climate adaptation and
GHG mitigation is also discussed
2) The role the cement industry plays in Indias economy and energy consumption is
discussed in Chapter 3. The manufacturing process as well as carbon mitigation
strategies being implemented by the industry in India is emphasized. The chapter ends
with a material flow and life cycle analysis of concrete for Rajkot, India but generally
applicable to any city in the state of Gujarat.
3) In Chapter 4 the methods and results of a small demonstration of a pervious concrete
system that occurred in Rajkot, India is disclosed as Phase I of the pervious concrete
project. This part of the study led to a concern over comparisons in strengths between
cube and cylinder samples. As such Phase II is used to discuss the attempt at establishing
a relationship between cubes and cylinder properties.
4) In Chapter 5 Phase I of the HVFA fly ash study involves a comparison between typical
fly ash properties in India and the U.S. and is used to discuss the importance of design
and test of high volume fly ash concrete mixtures. Cubes and cylinders strength results
are compared for the U.S. and India as part of Phase II. Phase III is used to identify the
benefits of high volume fly ash concrete over ordinary Portland cement concrete when
subjected to representative temperatures of hot days experienced throughout arid and
semi-arid regions of India. The chapter describes a multiple linear regression analysis
used to determine the effects of a variety of experimental conditions and compositions on
17


ordinary Portland cement concrete mixtures versus high volume fly ash concrete
mixtures.
6) The study ends with Chapter 6. A summary of the major findings are discussed as
well as recommendations on how to improve on the study.
18


2. Case Study Location: The City of Rajkot India
2.1 Demographics, Population, and Climate
Rajkot is located in the state of Gujarat in Western India (Refer to Figure 2.1).
The climate of Rajkot is hot and dry throughout much of the year thus representing a
semi-arid region. Mild temperatures can be about 20C (68F) but during the summer,
during the months of March through June, temperatures range between 24C to 42C
(75.2F to 107.6F). Rajkot can experience acute droughts at times but, during the
monsoon period (June to September) the city can receive an average of 500 mm (19.7 in.)
of rain.
Figure 2.1 Location of Rajkot within the state of Gujarat, India (Google Maps)
19


The population of Rajkot according to a 2001 census was approximately
1002,000 and has increased to about 1.4 million. A growth rate of 79.12% was
established in the 2001 census for the years (1991 to 2001) but was partly attributed to
extending the city limits to include other villages. Rajkot city is connected to other parts
of the country by air, two railway stations, and major roads that link Rajkot to several
cities within the state including to the state capital Ghandinagar. Rajkot is considered an
industrial town and the economy is based on over 400 foundries, engine oil
manufacturing, machine tools, engineering and auto works, castor oil processing Jewelry,
handicrafts, clothing, medicines, and agriculture (Rajkot Municipal Corporation, 2006).
A combination of Rajkots average growth rate of 3% and Rajkots identity as an
economic, industrial, and educational center has led to continued urbanization and the
need for a comprehensive development plan. Rajkot Municipal Corporation city
development plan for the years 2005-2012 was developed under the Jawahar Nehm
National Urban Renewal Mission (JnNURM) such that the goal of the city was identified
as being responsive, economical, efficient, productive, and equitable. While under the
mission of the JnNURM, Rajkot has also committed to incorporating clean development
strategies so that infrastructure investments would lead to an improved urban
environment and sustainable city. Recognizing JnNURM5 s mission ICLEFs (Local
Governments for Sustainability), South Asia Urban Climate Project has been working
with Rajkot to begin implementing sustainable infrastructure interventions that address
the infrastructure problems identified in the city development plan.
20


2.2 Rajkot Construction and Concrete Infrastructure
At least 5.5% of Rajkots population is employed through the construction
industry. The highest employment (28% of total population) occurs within the sector of
manufacturing. Rajkot does not have a cement manufacturing plant within city limits.
The closest plant is located about 116 km (72 mi) outside of the city in the area known as
Sikka. According to the Cement Manufacturers Association of India 7 other large
cement manufacturing plants are located within the state of Gujarat and the farthest plant
about s 295 km (183 mi) from Rajkot. Cement in Rajkot is used for various construction
materials such as reinforced cement concrete, prestressed concrete, paver blocks, cement
blocks, and asbestos piping. Figure 2.2a and 2.2b shows an example of paver blocks
made in Rajkot.
b)
Figure 2.2 Paver Blocks (a) Removal from Molds (b) Design on Surface of Blocks
Major cement companies that deliver cement throughout the state of Gujarat are Hathi
Cement (part of SaurashtraCement Limited), Gujarat Sidhee Cement Limited, UltraTech
Cement Limited (part of the Aditya Birla Group)Ambuja Cements Ltd.Shree Digvijya
Cement Co. Ltd., HMP Cements Ltd, Sanghi Industry Ltd., JK Lakshmi Cement Ltd.,
and Jaypee Cement (CMA2010c). There is one ready mix concrete plant within the city
limits which is owned and operated by the cement manufacturing company known as
21


Lafarge. Ready mix concretein Rajkotis only used in large construction projects.
Large construction projects are associated with bridgesfly oversrailwayskyscrapers
and bus rapid transit system (BRTS) roads (M. Joshi and Mr.Irish [contractor] personal
communicationMarch 8, 2011).The majority of the construction seen in Rajkot used
the method of on-site mixing.
2.2.1 Personal Account of Construction
Collaborative work with Rajkot Municipal Corporation allowed for personal
observations and communications to be made with a city assistant engineer and city civil
engineer as well as a structural engineer/owner of Lakhlani Associates. Additionally the
collaborative work allowed for the majority of the field research, presented in this
dissertation, to be performed on-site where a water/tower (designed by Lakhlani
Associates) was being constructed. The construction process of the water tower revealed
the following about most of the city concrete construction projects:
Ready mix is expensive compared to on-site mixed concrete and is not considered
necessary for all city projects
Cement bags and aggregate are delivered in bulk to the site (Refer to Figure 2.3
for example of stock piled materials)
Most common cement used on-site was Hathi, Ambuja, UltraTech, and Sidhee
cements
At this particular site water used for concrete mixture design was taken from a
bore well drilled on site
22


Each batch required that aggregate be weighed using a large scale located on site
that was calibrated daily. (Refer to Figure 2.4)
Concrete was mixed with portable diesel powered commercial concrete mixers
(See Figure 2.5)
Mixed concrete was transported by wheelbarrows or up several heights by a
bucket and pulley (See Figure 2.6 and Figure 2.7).
Bamboo was used for scaffolding and concrete forms
Both men and women worked and lived on-site
Most of the laborers were from villages nearby
Not all laborers had safety equipment to wear.
The laborers who worked with the placing of steel reinforcement are considered
skilled workers and get paid more than those working with just concrete
Figure 2.3 Materials Stock Piled Directly on Construction Site
23


Figure 2.4 Large Scale Used for Measuring Aggregate and Cement before Batching
Figure 2.5 Materials Transferred from Scale into Portable Diesel Powered Mixer
Figure 2.6 Laborers Placing Concrete
24


Figure 2.7 Cement Being Emptied from the Bucket and Pulley Machinery
2.2.2 Rajkot Concrete Infrastructure
In 2001 the city of Rajkot occupied an estimated 10,485 hectares (25906 acres) of land.
Figure 2.8 displays the breakup of land use in Rajkot. About 74% of the city limits were
developed, with residential areas occupying a little more than half of the developed (i.e.
residential, commercial, industrial, transportation, public, recreational, and other) area.
Commercial use is mostly reserved for retail marketing, industrial use includes 369 units
of various industries within the city limits and public use include hospitals, schools, and
government office buildings.
Investment on infrastructure projects in Rajkot occurs in the sectors of traffic and
transport, water supply, drainage, stormwater drainage, housing and the urban poor,
public works, and solid waste management. The majority of built infrastructure is
constructed of concrete. The typical concrete infrastructure seen in Rajkot can be
described as follows and are depicted in Figures 2.9 through 2.14:
Recreational/Office/Home/ Apartment Buildings
Roads
Sidewalks
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Wastewater Treatment Plants
Check dams
Water piping systems
Bridges
Water Towers
Total Land =10485 Hectare
6%
1 Hectare = 2.471 Acres
Figure 2.8 Breakup of Landuse within City Limits of Rajkot
(Rajkot Municipal Corporation, 2006)
26


Figure 2.10 Indoor Stadium
Figure 2.11 Buildings Near the Center of the City
Figure 2.12 Waste Water Treatment Plant
27


Figure 2.13 Construction of Housing
Figure 2.14 Construction of a Water Tower
Concrete plays a major role for the infrastructure found in Rajkot. Despite on-site mixing
seemingly lagging in terms of modern constructionIndian structural engineers have been
successful in demonstrating the advantages of concrete design for structures. The indoor
stadium was designed by Lakhlani Associates and in 2005 Mr. Lakhlani received the R
H Mahimtura Award For Excellence In Strucutral Engineering due to the innovative
structural system designed for the stadium. One unique aspect that made the design
innovative was a reinforced concrete tripod system which has the purpose of transmitting
roof forces to the ground. The stadium is just one example of how Rajkot has a
distinctive type of city management that is eager to collaborate with private and
government entities to try new ideas that allow the city to advance in terms of
28


technologybusinessindustryand infrastructure. In fact the city development plan for
2005-2012 expresses Rajkots goals in developing infrastructure that will reduce GHG
emissions and energy consumption and achieve a productive, efficient, equitable, and
responsive city which is part of the Government of Indias Jawaharlal Nehru National
Urban Renewal Mission (JnNURM).
2.3 Future GHG Mitigation and Climate Adaptation Goals
Rajkot has already demonstrated how the goals of the city development plan are
being achieved. On the roofs of many buildings in Rajkot, evacuated tube solar water
heaters have been installed (See Figure 2.15). This type of device has been used for some
years and is currently cheaper than gas water heaters; consequently it avoids C2 that
could result from gas powered water heaters. At the Rajkot Municipal Corporation
western zone office a solar photovoltaic system was installed to partially power the
office. Also, one of the Rajkot Municipal Corporation offices was designed with an open
foyer so that the various floors were cooled through passive cooling. Figure 2.16 shows
the open foyer which included a nice landscaping of plants. Other interventions that were
being implemented during 2011 was the construction of a Bus Rapid Transit System
solar powered lights for parks, investing in energy saving technologies for schools, and
installing more city trash bins in communities throughout the city for waste collection.
Some of the interventions were a result of the collaborative work with ICLEI South Asia.
The collaboration was meant to showcase clean and efficient technologies for
infrastructure and to find what could be successful for the city as a long term method of
use or design. Rajkot has been willing to implement new ideas into their infrastructure
design even before collaborating with ICLEI South Asia. As stated in the city
29


development plan some of the priorities of the city have been improvement of roads and
stormwater management. The city has experimented with stormwater management
methods and fly ash concrete roads.
Figure 2.15 Tube Solar Water Heaters Mounted on the Roofs in Rajkot
Figure 2.16 Rajkot Municipal Corporation Office with Passive Cooling Foyer
Design
30


2.3.1 Stormwater/Rainwater Harvesting
Through a personal communication with Y. K. Goswami (March 9, 2011)
Assistant Engineer at Rajkot Municipal Corporation, Rajkot has been involved in urban
rainwater harvesting or stormwater management trials. For example within certain
residential areas, parks or gardens have been built such the park acts like a recharging pit
or detention pond when it rains. In Figure 2.17 an example of one of these parks can be
seen before it is filled by stormwater. The purpose of these parks is to direct the
stormwater into these pits so that the water either seeps into the ground or in some cases
drains into a storage tank below constructed below the park. The depth excavated for
these parks will vary based on the rain events expected for an area. In Figure 2.17 it
appears as though the depth is at least 1.2 m (4 ft). Figure 2.18 shows the same park after
storm water had drained into the park. The rain event filled the total depth of the park.
Figure 2.17 Recharging Pit or Detention Pond Park Being Cleaned
31


Figure 2.18 Park Filled with Stormwater After a Rain Event
2.3.2 HVFA Concrete Road Project
In 2005 Rajkot finished construction of the citys first fly ash concrete road. The
project was completed in partnership with Ambuja Cement, Natural Resources of
Canada, and the Confederation of Indian Industry. The project used a high volume fly
ash concrete mixture design. The mixture design demonstrated that initial costs for
concrete roads could be reduced through the use of local materials and waste products
such as fly ash. The project presented an alternative to bituminous roads. The road
extends 2.3 km (1.4 mi) through the campus of Saurashtra University in Rajkot. The
material design included grade 53 ordinary portland cement (OPC) from Ambuja
Cements Ltd. and fly ash from Sikka thermal power plant located in Sikka, Gujarat,
which is about 115 km (71 mi) from the city of Rajkot. Two concrete layers made up the
design of the road, such that the 150 mm (o inj thick bottom layer was from a 50% high
volume fly ash concrete mixture and the 50 mm (2in) thick top layers was made from a
30% fly ash concrete mixture. The top and bottom layer reached a compressive strength
of about 41.2 MPa (5976 psi) and 40.1 MPa (5816 psi) respectively. Design compressive
strengths for concrete roads in the U.S. generally are at least 28 MPa (4000 psi) and
Rajkot5s road project was at least 12 MPa (-1800 psi) greater than the design
32


compressive strength. Figures 2.19a and 2.19b show the surface of the concrete
pavement 6 years after it had been constructed. Although Figure 2.19a shows a two-
wheeler and tractor using the road, heavier traffic such as commercial vehicles can be
expected on the road as well. Figure 2.19b shows the different wearing down of the
surface of the concrete. The project brought about other concrete pavement construction
and in 2011 a high volume fly ash concrete road was being constructed around the Raiya
waste water treatment plant in Rajkot (See Figures 2.20a and 2.20b).
b)
Figure 2.19 HVFA Concrete Road on Saurashtra University Campus (a) Two
Wheelers and Tractor on the Road (b) Close up of the Surface of the Road
b)
Figure 2.20 Raiya WWTP Site (a) Placing Concrete (b) Curing Concrete
33


2.3.3 Collaboration between UC Denver, ICLEI South Asia and Rajkot Municipal
Corporation
As part of Rajkots collaboration with UC Denver and ICLEI South Asia it was
decided that there was further interest in trying new stormwater management systems or
best practices and the need to further study the compressive strength with high volume fly
ash concrete. Originally all parties preferred an actual field installation of a pervious
concrete system and anticipated the results for compressive strength, water percolation,
and water quality improvements. The parties agreed that the pervious concrete field
demonstration would be constructed at the Raiya WWT site where the fly ash concrete
road was being placed. As part of the fly ash concrete project there was significance
placed on determining whether other local fly ash sources (besides the Sikka power plant
fly ash used in Saurashtra University road) would produce similar compressive strengths.
There was an overall interest in promoting the use of these concrete technologies to
facilitate reforms and improvement of urban infrastmcture for cities interested in climate
adaptation and carbon mitigation (carbon mitigation through quantification of reduced
GHG emissions from use of the pervious concrete and fly ash concrete). The remainder
of this dissertation will discuss the collaboration between parties in detail.A material
flow and life cycle analysis (MFA-LCA) of cement and concrete will be discussed in
Chapter 3. The MFA-LCA was modeled after the study conducted by Reiner (2007) with
the goal of determining the contribution that cement use had in cities such as Rajkot.
Chapter 4 provides the discussion of the potential applications of pervious concrete in
Rajkot for stormwater management while Chapter 5 discusses the potential for HVFA
34


concrete to be used as a climate adaptation strategy in extreme hot weather conditions
that could occur in a semi-arid region like Rajkot.
35


3. Carbon Mitigation Through Concrete: An MFA-LCA Approach
3.1 Bottom-line: Cement and Concrete Manufacturing in India and the US
The objective of this study was to quantify C2 emissions resulting from Indian
cement manufacturing and concrete production and compare results to the U.S.
Literature reported different cement emission factors ranging from 0.6 to 1.0 tonne of
CCVtonne of cement (0.6 to 1.0 lb C2/lb cement) (e.g. WBCSD2010; ParikhSharma
Kumar, Vimal, IRADe, 2009). It was unclear which would be the most appropriate
emissions factor. Thus initial findings resulted in the review of Grasim Industries
sustainability report published for the year 2007-2008. Grasim, ACC Ltd. and Ambuja
Cements Ltd. are major competitors in Indian cement manufacturing. Both Grasim and
Ambuja are providers of cement products to the state of Gujarat. Grasim5 s report was
also one of the only available reports that had created a C2 emissions and energy
inventory that could be compared to the thorough inventory published for the U.S.
cement industry by the Portland Cement Association (Marceau, Nisbet, VanGeem, 2010).
Grasim5 s report presented a consolidated (including subsidiary companies)
account of total materials, energy, and electricity used in the year. In addition, C2
emissions for direct energy (thermal energy) and indirect energy (purchased electricity)
were calculated. Grasim5 s report indicated that all cement manufacturing plants had been
converted into the dry precalcination process. There are three main processes for
manufacturing cement and each are discussed later in this chapter. However, the dry
precalcination process is currently the most energy efficient process available for cement
manufacturing (about 1.3 GJ/tonne of clinker [559 Btu/lb clinker] more efficient than the
36


wet process). The precalcination process makes use of the waste heat from the kiln and
clinker cooler to preheat the kiln material by use of cyclone preheaters installed before
the kiln (up to 6 cyclones can be installed). Both in the U.S. and India the dry process is
used to produce more than half the total cement produced, however the dry process in the
U.S. only accounts for 53% of total production, but in India it is 98% (Maceau et al.,
2010 and CMA2010c). Table 3.1 compares the direct and indirect energy consumption
for India (represented by Grasim) and the U.S. through the dry precalcination process.
Table 3.1 Comparison of Energy Use per Tonne of Cement Between the U.S.
Cement Industry and Indias Grasim Industries. ________________________________
Energy Source Dry Precalcination Process GJ/Tonne of Cement
u. s. India (Grasim) * India (Grasim)
Coal 2.7 2.8 2.4
Gasoline 0.0034
Liquefied Petroleum Gas 0.00039 --- ---
Middle distillates 0.053
Ui D c Natural gas 0.28 --- ---
Petroleum coke 0.47 0.60 0.50
i-H Residual oil 0.0026 --- ---
Wastes 0.24 0.022 0.018
Furnace Oil --- 0.100 0.083
Diesel 0.025 0.021
Lignite --- 0.020 0.017
Indirect Energy Purchased Electricity 0.52 0.18 0.15

Total 4.2 3.8 3.1
* Values are in GJ/Tonne of cementitious material
1 GJ/Tonne of cement = 429.92 Btu/lb of cement
Source: Marceau, Nisbet, VanGeem, 2010; Grasim Industries Ltd, 2008
An overview of an LCA is given in the next section, but a key step in an LCA is
choosing a functional unit. In order to relate inputs and outputs of the cement
37


manufacturing process from two different countries the functional unit has to be the
same. The functional unit for the LCA (cradle-to-gate) given in Table 3.2 was a unit
mass (i.e. tonne) of cement. It is important to note that Grasims report actually reported
final emissions in terms of tonnes of C2/tonne of cementitious material. Cementitious
is used to represent the use of alternative materials that are used in replacement of a
percentage of cement. These materials can be fly ash, silica fume, or slag. In the U.S.,
the use of these materials is usually called blended cements (Type IP, Type IS, Type
I(PM), and Type I(SM) where P = pozzolana, S = slag, M = modified) and in India these
cements are called portland pozzolana cement (PPC) (when fly ash is used) and portland
blast furnace slag cement (PBFS). Blended cement production in the U.S. is about 2 to
3% of total production while in India it is about 60 to 70% (USGS, 2010; CMA 2010c).
Use of these cementitious materials ideally reduces cement clinker demand for a unit
mass of cement product as a result of less kiln fuel being burnt. Additionally, use of
cementitious materials avoids disposal or stock piling of fly ash and slag. However,
emissions do arise from transportation of the fly ash and slag to the cement
manufacturing site and additional emissions may occur from any grinding that is
necessary for slag. Since India produces large amounts of cementitious materials
including it as the functional unit in a life cycle inventory as Grasim did is a benefit.
However, it is not necessary because if there has already been a reduction in thermal and
electrical energy due to less clinker is being processed this would be reflected in the
inventory without using cementitious as the functional unit.
In Table 3.1 direct energy for the U. S. and Grasim does not always come from
the same fuels. According to Grasim5s sustainability report fuels such as gasoline and
38


natural gas are not used as they are in the U.S. However, the coal consumption appears
to be similar and there is about a 20% difference in the use of petroleum coke. Often use
of alternative waste fuel materials (which are discussed in detail later in this chapter) in
the kiln reduces carbon dioxide emissions. In this case, the U.S. cement industries on
average use more waste materials as kiln fuels compared to Grasim. For indirect energy,
there is a large difference in electricity purchased between Grasim and the U.S. Grasim
uses about 65% less purchased electricity compared to the United States. In India captive
power plants generate electricity on-site and reduce the need to purchase electricity from
state grids. Overall Grasim uses approximately 10% less energy in the manufacturing
process compared to the average cement industries in the U.S. that use the precalcination
process.
Table 3.2 Summary of Energy Use and Emission Factors from Direct and Indirect
C2 Emissions between India and the U.S.
Attribute U.S. India (Grasim)* ** India (Grasim)*
Functional Unit Cement Cement Cementitious
Thermal Energy Use (GJ/tome of cement) 3.7 3.6 3.0
Purchased Electricity Use (kWh/tonne of cement) 144 51 42
^Electricity EF flat CO2/tonne of cement) 98 44 36
**CementEF (kg CO2/tonne cement) 867 855 708
* India has smaller emissions from electricity due to use of captive power on-site
**This number is net electricity purchased, however, with the inclusion of indirect
emissions this leads to about a 7% increase in emissions for the U.S. cement
manufacturing.
1 GJ/Tonne of cement = 429.92 Btu/lb of cement,1 kWh/Tonne of cement =1.54 Btu/lb,
1 kg/tonne = 2 lb/short ton
Table 3.2 uses the data from Table 3.1 to calculate electricity and cement (net
purchased electricity) emission factors. In additionthe emission factors reflect how
39


using different fuels and different methods of attaining electricity can change the result of
the emissions. Grasims captive power plantsfuelsand use of cementitious materials
help the industry reduce cement emissions by about 12 kgCCVtonne of cement (24
lbC2/short ton of cement) or about a 2% reduction. If purchased electricity was
included in the cement emission factor the reduction is greater for Grasim, about a 7%
percent difference. Also it might be important to note that if the functional unit was
cementitious materials than Grasim shows a larger reduction in emissions.
As stated previously the concrete emission factor for India was also important.
Currently no published research could be found regarding an emission factor for concrete
in India. In the U.S. two studies have reported a thorough inventory for concrete
production. The study by Reiner (2007) discusses two different methods used to
calculate a concrete emission factor. Using the software program Building for
Environmental and Economic Sustainability (BEES) Version 3.0 Reiner estimated a
concrete emission factor to be 0.17 tonnes CCVtonne concrete. Reiners study improved
on the BEES estimated concrete emission factor through the development of a life cycle
analysis for concrete used in the city of Denver, Colorado. Through his LCA the
concrete emission factor for a common type of concrete used in Denver (Class B) was
estimated to be 0.22 tonne C2/tonne of concrete. Reiner demonstrated that the concrete
emission factor will vary due to the reality of different concrete mixture designs. The
second study, contracted out by the U.S. Department of Energy (2003), calculated a
concrete emission factor equal to about 0.15 tonne CCVtonne concrete.
Both studies by Reiner and the U.S. Department of Energy quantified concrete
emission factors by gathering data from cement, aggregate, transportation, and ready
40


mixed operations. In India ready mixed concrete operations are not the commonly used
method to produce concrete. As will be discussed in this chapter site-mixed concrete is
the main method of producing concrete in India. Throughout this chapter, the
development of a LCA (cradle to gate) for concrete will be discussed. Although
Grasims sustainability report presented a reasonable accounting of C2 emissions it was
decided by the author that a cement emission factor should be calculated to represent the
majority of the companies that provide cement to concrete construction projects in
Rajkot. The remaining sections in this chapter will discuss the energy consumption and
efficiency methods being used by Indian cement manufacturingthe energy and C2
emissions for aggregate processing, transportation of materials, and on-site mixing of
concrete. Finally a concrete emission factor will be calculated for a conventional
concrete mixture used in Rajkot, and for pervious and high volume fly ash concrete
mixture designs in order to show the environmental advantages of using pervious
concrete and high volume fly ash concrete.
3.2 Life Cycle Assessment of Cement and Concrete in India
Tools such as an environmental life cycle assessment (LCA) can be used to assess
certain environmental impacts (i.e. GHG emissions) that are associated with the different
phases of a material or product. An LCA tool can also be applied as a strategy for
determining how GHG emissions can be reduced to moderate the impacts of climate
change. GHG are gases that trap heat in the atmosphere and are represented by global
warming potentials (GWP) in C2 equivalents (C2eq). Carbon dioxide (C2) is the
baseline and has a global warming potential of 1;methane (CH4) has a GWP = 21; and
nitrous oxide (N2O) has a GWP = 310 (IPCC2007a). Chlorofluorocarbons (CFCs)
41


hydrofluorocarbons (HFCs), hydrochlorofluorocarbons (HCFCs), perfluorocarbons
(PFCs), and sulfur hexafluoride (SF6) have high GWPs and range from 90 to 23,900.
The use of concrete in urban areas of India (i.e. Rajkot) is the focus for this
dissertation. In this chapter C2 impacts are quantified for concrete such that the
boundary of the LCA begins with the manufacture of cement up to the concrete
production method used most commonly in cities in India (i.e. site-mixed concrete).
Insufficient literature exists on site-mixed concrete, but this study will be one of the first
to apply the method of LCA to site-mixed concrete. In addition to the development of an
appropriate LCA model this chapter will show the CO2 impacts of urban structural
concrete mixture designs. These impacts will be compared to those calculated for
previous concrete and high volume fly ash concrete to demonstrate the reduction in CO2
that can be expected with the two sustainable concretes.
An LCA takes into account energy, material inputs, and environmental releases
from material acquisition, product manufacturing, transportation, use, maintenance, and
disposal and/or recycling. In this dissertation the impacts from a cradle-to-gate (resource
extraction to the product leaving the manufacturing process) and the product use phase
are quantified. The end of life of the product is not considered in this study.
In a LCA study on high performance concrete Reiner (2007) describes three
different models (process based, economy input/output [eio], and hybrid [combined
process and eio]) used to complete an LCA. This dissertation uses the process based
LCA model such that the inputs (materials and CO2 energy resources) and the outputs
(CO2 emissions) are itemized for producing concrete in India. The following
methodology was used to complete the LCA model:
42


Goal and scope defined -India is one of the largest producers of cement,
however, not all the cement companies follow the same protocol for
determining C2 emissions. Therefore, within this study the process-based
LCA model will be used to quantify CO2 emissions from fuel consumed in the
cement manufacturing process. Calcining emissions that occur at the kiln will
also be taken into account. The emissions from electricity are included from
cement manufacturing as well. For the first the time, an emission factor will be
calculated for the production of site-mixed concrete. This will also involve the
emissions from fuel consumption during crushing of aggregatetransportation
of aggregate, transportation of cement, transportation of fly ash, and operations
of the portable cement mixer. The functional unit is one tonne of concrete
Inventory analysis A description of the materials and processes used to make
concrete is described throughout this chapter and the system boundary is shown
in Figure 3.1
Impact Assessment The only greenhouse gas taken into account for the
quantification of emissions is CO2. The other five gases that can contribute to
GHGs (methanenitrous oxidehydrofluorocarbonssulfur hexafluorideand
perfluorocarbon) will not be included in this initial emissions study for Indian
concrete. Normally these gases would be taken into account but there is limited
information on these gases for cement manufacturing in India and carbon
dioxide emissions are usually more significant than the emissions from methane
and nitrous oxide.
43


Interpretation step The development of a model that can be used to determine
the environmental impact of using a certain concrete mixture design will be
useful in understanding which alternative mixture designs can provide the same
serviceability and durability as well as reduce the environmental impacts.
Material Extraction
and Processing
Concrete Processing
Cradle-to-Gate
f
*(Figure design adapted from Reiner2007) Dotted line represents the citys
environment, while the arrows represent the transportation used throughout the entire
flow of materials.
Figure 3.1 Life Cycle Phases and Material Flow for Concrete in Rajkot
3.3 Understanding the Cement Production and Concrete Industry in India
The production of cement is about a century old in India. The first cement
industry was established in Porbundar, Gujarat in 1914 (DRPSCC, 2011). Table 3.3
shows how India compares within the top 19 cement producing countries/regions in the
world for the year 2010. In 2010 India was the second largest producer. In Figures 3.2
and 3.3 the trend in cement production and potential cement consumption for four major
cement producing countries are shown. Japan and India are unique in Figures 3.2 and 3.3
because Japan currently has the highest kiln capacity (3370 tonnes per day) and is first in
energy efficiency while India is second in both categories. Despite, India being a major
44


producer of cement the national per capita consumption is 0.136 which is lower than the
world average which is about 0.48 and lower than that seen in China, U.S., and Japan
(Refer to Figure 3.2 and Table 3.3). However, India being one of the most populous
countries and having an increasing economy have led the cement industry analysts to
state that the slow increase in per capita cement consumption is just an indicator of the
industrys growth potential (Ernst & Young2011).According to the Cement
Manufacturers Association (CMA2010c) India has approximately 142 large cement
plants together producing at least 161 million tonnes of cement a year. Two major
companies ACC Ltd. And Ambuja Cements Ltd. withdrew membership from CMA thus
there production is not included in CMAs statistics presented in Table 3.4. In fact
during the 2009-2010 year Ambuja produced 20.1 million tonnes of cement while ACC
Ltd. produced 21.4 million tonnes. The Indian cement industry has three types of cement
units which are large, white, and mini cement plants. The mini plants use vertical shaft
kilns with cement production not exceeding 109,500 tonnes/year (120701 ton/year [ton =
U.S. short ton]) and are plants that use the rotary kiln such that cement production does
not exceed 300,000 tonnes/year (330690 ton/yr). Within this research the focus is
pertaining to large cement plants.
According to an article in the Indian Concrete Journal, concrete was identified as
the preferred construction material in India (Kumar & Kaushik2003). Between the
years 1998-2003 major construction projects that utilized concrete were fly-oversmetro
railsatomic and thermal power plantsroad projects and the rebuilding of infrastructure
in Gujarat after the destructive earthquake in January 2001.In 2002 concrete
consumption in India was estimated at 190 million m3 (249 million yd3). A. K. Jain
45


estimated that the rate of consumption of concrete should increase by at least 19.5 million
m3 (26 million yd3) per year and ready mixed concrete should account for 11.0 million m3
(14 million yd3) of the total concrete produced in India by 2012 (as cited in Kumar &
Kaushik2003). Howeverin 2008 the Indian Ready Mixed Concrete Manufacturers
Association (RMCMA) estimated that 20 to 25 million m3 (26 to 33 million yd3) of
concrete were produced annually among 400 to 500 ready mixed facilities (RMCMA
2008). Although the ready mixed concrete industry in India is growing, the ready mixed
concrete business in India is still emerging and only accounts for 5% of concrete
consumed in India while the rest of concrete is site-mixed.
Table 3.3 World Cement Production 2010
Rank Country/Region Million Tonnes
1 China 1880
2 India 210
3 United States 67.2
4 Turkey 62.7
5 Brazil 59.1
6 Japan 51.5
7 Russia 50.4
8 Iran 50
9 Vietnam 50
10 Egypt 48
11 South Korea 47.2
12 Saudi Arabia 42.3
13 Thailand 36.5
14 Itafy 36.3
15 Mexico 34.5
16 Pakistan 30
17 Germany 29.9
18 Spain 23.5
19 Indonesia 22
20 Others 480
Total World 3310
(USGS, 2012)
46


China
India
U.S.
Japan

China
India
U.S.
Japan
Figure 3.3 Potential Trend in Per Capita Cement Consumption for Four Leading
Cement Producing Countries (USGS, 2012; Parikh, et al,2009; United Nations
2010b)
Figure 3.2 Trend in Cement Production for Four Leading Cement Producing
Countries (USGS, 2012; Parikh, Sharma, Kumasr, Vimal, IRADe, 2009)

000000000
00000000
64208642
11 11 11 11
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UOLPIlpoJJ^Ualua0
li\
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o o o o o o o
2 0 8 6 4 2 0
11 11 o o o o o
{Sld2 bd}
uoudlu=suouJlwuwu--mJU-o^
47


Table 3.4 Indian Cement Industry Information
India Cement Industry (Large Plants)
Cement Companies 47 Nos.
Cement Plants 142 Nos.
Installed Capacity 222.61 million tonnes
Production 160.75 million tonnes
Domestic Despatches 158.25 million tonnes
Per Capita Consumption 0.136 tonnes/person
(CMA 2010a; CMA 2010c)
3.3.1 Ready Mixed Concrete Industry in India
The first ready mixed concrete batching plant was established in the city of Pune,
India in 1987. The batching plant closed shortly after being unable to meet the demands
of large projects like the Tanji Wadi subway, which led to skepticism in the RMC market
in India (Alimchandani, 2007; Gordon & Kshemendranath, 1999). The first successful
ready-mix concrete plant was ultimately set up 7 years after the Pune plant by ACC Ltd.
(cement company) in Mumbai. Unitech Ltd. and RMC Group Pic soon followed with
more ready mixed plants in Mumbai. However, even these RMC plants faced barriers
because machinery and operations were not as sophisticated in comparison to plants
established in Europe or South East Asiaagencies that could provide maintenance and
technical support to plants were not well established in India, poor quality of aggregates
led to inconsistent mixturesthe construction industry and contractors did not know how
to schedule or plan for the use of ready mixed concrete, lack of specifications meant
specifiers were reluctant to recommend a product they were unfamiliar withand there
was need to invest in training a workforce (Gordon & Kshemendranath1999). Since
1994, the RMC industry has grown modestly. The perception of the RMC remains
inconsistent since only a few companies have made the ready mixed industry their core
48


business while others such as cement companies, who own RMC companies, think of it
as downstream activity for the main business of cement manufacturing (Gordon &
Kshemendranath). Today, most RMC plants are located in major cities such as Delhi,
Ahmedabad, Mumbai, Bangalore, Chennai, Kolkata, and Hyderabad where RMC
accounts for 30 to 60% of total concrete used in the cities. To help encourage the growth
of the RMC industry the RMCMA has been working towards guaranteeing quality RMC
products through certification of plants around the country.
3.3.2 Site Mixed Concrete in India
The advancement of the construction industry in India has been slow due to many
factors. Historicallyconstruction in India was heavily dependent on government funding
for infrastructure before Indias government began encouraging private investment into
developing infrastructure in 1991. As a result of construction projects being subsidized
by the government, timelines for completion of the projects were not enforced,
bureaucratic processes caused delays for constructionand the quality of construction
projects was affected. Todayoutdated construction techniques and specifications are
still used. Site-mixed concrete still uses portable concrete mixers, human chains and
wheelbarrows to transport the concrete, concrete buckets are lifted by mechanical winch,
and steel rods are still being used for consolidation and compaction of concrete instead of
vibrators. Many RMC companies encourage the use of RMC over site-mixed concrete
and often list the following disadvantages of site-mixed concrete (Gordon &
Kshemendranath, 1999; Lafarge, 2012):
The consistency and reliability of mixtures is dependent on the frequency of
sampling and testing the variability of each mixture which is also dependent on
49


the variability occurring with the manual mixing of individual proportions of 50
kg (110 lb) bags of cement
The volume of concrete production within an 8 hour shift is dependent on the
skills of the laborer.
Manual mixing is more time consuming
The quality of raw materials is manually checked or not checked at all
Raw materials are often wasted
More money is spent on time, effort and laborers
Untrained and unskilled laborers create dangerous conditions and there is a lack
of proper supervision
Since materials are stored on-site there is the likelihood that stock of materials can
be stolen.
Although, RMC companies make reasonable claims against site-mixed concrete RMC is
still12 to 20% costlier than site-mixed concrete. Additionally site-mixed concrete is still
the dominant method used in construction in India especially for rural and developing
urban areas as was seen with the city of Rajkot. Site mixed concrete is a major source for
employment opportunities. The inclusion of site-mixed concrete in construction
contributed to Indias construction industry being recorded as the largest employment
sector in 2000, thus employing 16% of the work-force available in India. This is
significant in comparison to a 6 to 8% employment of the working population in
developed countries (The Indian Concrete Journal, 2004).
50


3.3.3 Indian Concrete Mixture Designs
Specifications up until the year 2000 were still based on 1950s construction techniques
and old British Standards such that structural concrete was based on Ml5 and M20
grades of concrete. The batching occurred by volume, thus meeting a certain nominal
ratio by volume for each grade of concrete. This meant minimum strengths had to
achieve 15 MPa (2176 psi) and 20 MPa (2901 psi) respectively (Kumar & Kaushik,
2003; Gordon & Kshemendranath1999). Today, these same mixture designs are
commonly used for structural purposes in rural and developing urban areas. But as RMC
concrete becomes more mainstream, specifications are revised to include more leeway for
design mixed concrete, the roles of aggregate properties are better understood, benefits
are seen with lower water cement ratios, and with research and development showing
improved concrete strength from lower cement contents new grades of concrete (M20
through M40) have been adopted by public works departments. Large construction
projects have been known to use M50 grade which is a form of high strength concrete,
high performance concrete, compacted reinforced concrete, reactive power concrete, and
self compacting concrete. High grades of concrete are often used in bridges, piles, high
rises, and power plants (Kumar & Kaushik, 2003). The use of waste materials or
byproducts has increased (i.e. ground granulated blast furnace slag, metakaolin, and fly
ash). Chapter 5 is dedicated to a discussion on fly ash use in Indian concrete. Table 3.5
lists example mixture quantities for common grades of concrete in India.
51


Table 3.5 Mixture Proportions for Typical Grades of Concrete (Based on Saturated
Surface Dry Conditions)___________________________________________________
Material M15 M20 M25 M30 M3 5 M40
Cement k^m3 270 290 320 380 400 400
Water kg/m3 135 145 138 160 160 160
Fine Aggregate kg/m3 711 696 751 711 704 660
Coarse Aggregate kg/m3 1460 1429 1356 1283 1271 1168
20 mm kg/m3 1051 1029 977 924 915 701
10 mm kg/m3 409 400 380 359 356 467
Admixture k^m3 0 0 1.6 1.9 2 2.4
water cement ratio 0.5 0.5 0.43 0.42 0.4 0.4
(Kishore, 2012)
Conversion to U.S. Customary units is 1 kg/m3 =1.686 lb/yd3
3.4 Cement Manufacturing Process in India
The manufacturing of cement in India is similar to the process described in a report
published by the Portland Cement Association which focused on the life cycle inventory
of portland cement manufacturing in the United States (U.S.) (Marceau, Nisbet,
&VanGeem2010). The process used both in India and the U.S. is described in four
major steps. Figure 3.4 shows the four steps in cement manufacturing, previously
described, for a cement company in India known as Grasim Industries Limited.
1. Limestone quarries located near the cement plants are mined, drilled, and
blasted to extract limestone. The limestone is cmshed to approximately 5 cm (2
in) and stored for blending.
2. The limestone is proportioned with corrective raw materials in order to achieve
the correct chemical composition. The materials are ground into a raw meal and
stored in silos. Additionally any materials used for fuel (coal, wastes, petcoke
and other alternative fuels) are processed, dried, and sized, blended and stored in
silos onsite as well.
52


Ltl
U)
Figure 3.4 Steps in cement manufacturing process at Grasim Industries Limited Cement Company (Grasim Industries
Limited, 2008)


3. The raw meal is fed into preheaters and then into the kiln systems. The fuel is
fed into the kiln for combustion. High temperatures in the kiln help remove
water from the raw meal, calcine the limestone, and cause necessary chemical
reactions to form clinker. The clinker is cooled and stored before grinding. In the
PC A report this stage is known as pyroprocess.
4. The clinker is moved from storage. It is ground to a fine powder with gypsum
and performance enhancer to make Ordinary Portland Cement (OPC). Fly ash or
slag can be added at this stage to make Portland Pozzolana Cement (PPC) and
Slag Cement, respectively. Cement leaves the plant in 50 kg bags or in bulk.
3.4.1 Phases of Cement Clinker
The process of making portland cement involves firing calcareous material (i.e.
limestone, chalk, marl, and aragonite) with siliceous, argillaceous, and ferriferous ore
materials (sand, shale, clay, and iron ore). The selection of raw materials is a meticulous
process because high concentrations of trace elements can cause problems in the plant or
in the final product. There are four main phases (Alit, Belie, tricalcium aluminate alkali
solid solution, and ferrite phase solid solution) in the OPC that form once raw materials
have reacted. Ideally the chemical compositions that represent these four phases are
tricalcium silicate (3CaO.Si2)dicalcium silicate (2CaO.Si2)tricalcium aluminate
(3CaO.Al203)and calcium alumino ferrite (4CaO.Al203.Fe203). These chemical
compositions are often abbreviated as C3S, C2S, C3A, C4AF such that C = CaO, S = Si2,
A = A1203, and F = Fe23 (Gani1997). A phase diagram (refer to Figure 3.5) is best
used to show how the relative proportions of the raw materials can direct the outcomes of
54


the phases and microstmcture of the clinker. In general,OPC should fall within a C3S,
C2S, and C3A triangle in a phase diagram (Gani, 1997).
S
Figure 3.5 Phase Diagram for Ordinary Portland Cement (Gani, 1997)
3.4.2 Kilns
The kiln plays an important role in contributing to the structure of the clinker and
forming the final product. High temperatures are required to form the complex mixture
of the clinker. The flame of the burner is approximately 2000C (3632F), the material
making up the clinker has minimum temperature of 1455C (2610F), and precalciners
are between 1000C (1832F) and 1200C (2192F) (WBCSD2005b; Gani1997). The
kiln is usually a large steel tube lined with refractory (i.e. bricks) and is inclined by about
3 to 5 from horizontal. The kiln rotates slowly (20 to 86 rph) as the raw materials are
fed into the top of the kiln. There are three main types of processes used in the
production of cement with a rotary kiln: wet, semi-dry, and dry process. In India between
55


2009 and 2010, 97.9% of cement produced by large plants was a result of using the dry
process, 0.5% of cement production was completed by the wet process, and 1.6% of
cement production was a result of other processes (CMA2010a). Within the wet process
the raw materials are fed into the kiln as slurry with 37%-39% moisture due to being
mixed with water. In the semi-dry process the raw material has 10%-15% moisture and
is partially calcined before entering the kiln. In the dry process the raw material is fed
into the kiln as a dry powder. Cyclone heat exchangers and precalciners located before
the kiln use the hot gases from the kiln to dry and partially calcine the raw materials. If
precalcined, in addition to dried and preheated, the production rate in the cement kiln can
be increased by 50/ to 70/. To accomplish precalcining a burner is constructed
between the kiln and the preheating cyclones. Precalcining can help extend the life of the
refractory by reducing some of the heating load that is required in the kiln (Gani, 1997).
3.5 Energy Consumption within the Cement Industry
The production of cement is an energy intensive process. Particularly in step 3, of
the cement manufacturing process, it was noted that high temperatures are required in the
kiln. The traditional kiln fuels burned (coal, petroleum coke, sometimes natural gas, and
fuel oil) result in an energy consumption between 3000 and 6500 MJ of fuel/tonne of
clinker (depending on the manufacturing process) (WBCSD2005b). Grinding and
milling are typically dependent on electricity and the pyroprocess might use electricity.
Purchased electricity consumption can amount to 0.52 million Btu/tonne of cement (153
kWh/ton of cement) (U.S. DOE, 2003). However, the global cement industry has the
opportunity to increase efficiency by 0.2% to 0.5% per year, by replacing outdated
56


equipment, converting to the dry process, and focusing on mineral and energy recovery
through use of wastes and by-products (WBCSD2005b).
3.5.1 Energy Scenario in the Indian Cement Industry
Indian industries such as steel, aluminum, and cement account for the largest
share in the demand for commercial energy. In 2007 industries had a 44.8% share in the
total energy consumption for India. The industry share could be further broken down
into cement accounting for 13.5%aluminum 11.4%steel 39.7%and others 35.4%
(Dutta & Mukherjee, 2010). The Indian cement industry is the second largest producer of
cement after China and has achieved world class efficiency following Japan5s cement
industry. Average kiln capacity is 2860 tonnes per day (3152 ton per day) which is 510
tonnes (562 tons) less than Japans kiln capacity (CMA2010a). The Indian cement
industry has made significant modifications to the process in order to reduce the energy
intensity. Technological upgrades have resulted in an average thermal energy
consumption of 725 kCal/kg of clinker (2.6 million Btu/ton) and an average electricity
consumption of 82 kWh/tonne of cement (0.3 million Btu/tonne) which is about 75
kCal/kg of clinker (0.3 million Btu/ton) and 17 kWh/tonne (0.05 million Btu/ton) of
cement more than that recorded for the best performing plant in the world (DRPSCC,
2011;CMA 2010a). In Table 3.6 energy use between India and the U.S. is compared.
Between 2009 and 2010 Table 3.6 shows that the U.S. cement industries operated
with lower energy efficiency than Indian cement industries. Additionally, India produced
more clinker and cement while achieving lower energy intensities in that same year. As
mentioned previously, India has invested in operational efficiency, process control, and
energy conservation by use of alternative raw materials and fuels, waste heat recovery
57


systemsogeneration systemscaptive power plantsand higher productions of blended
cement.
Table 3.6 Average Energy Use Between India and U.S. Cement Industry for 2009-
2010
Enei^y Source or Material Unit India U.S.
Fuel Ener Intensity GJ/tome clinker (million Btu/ton) 3.0 (2.6) 4.2 (3.6)
Electricity Intensity kWh/tome of cement (million Btu/ton) 82 (0.3) 144 (0.4)
Total clinker production million tome ^million ton) 128.3 (141.3) 56.1 (61.8)
Total cement production tome (million ton) 160.7 (177.1) 61.0 (67.2)
Total Fuel Ener^ million GJ (million Btu) 487.6 (462.1) 255.0 (241.7)
Total Electricity million kWh (million Btu) 13180.7 (45.0) 8784.0 (30.0)
Source India: (DRPSCC2011; CMA2010a)
Source U.S.: (MarceauNisbet& VanGeem2010; USGS2011)
3.5.2 Methods of Energy Efficiency
As seen in Table 3.6, the electricity used (per tonne of cement) by Indian cement
industries was about 57% of what the U.S. usea. in order to avoid purchased electricity,
Indian cement industries have established captive power plants (CPPs) on-site, where
cement manufacturing occurs. Within 2002 and 2004 the installed capacity of captive
power plants was growing faster than the countrys generation utilities (ShuklaBiswas
Nag, Yajmk, Heller, & Victor, 2004). A common reason for the growth in CPPs was the
advantage of having uninterrupted power for industrial processes. Unlike many of the
power generation utilities for the country the CPPs are owned by the industries and not
the government. However, in states such as Gujarat, permission to set up a CPP has to be
attained from the Gujarat Electricity Board. The size of the CPPs can vary, for example,
in the state of Gujarat, out of 163 CPPs in 2002, the smallest plant5 s installed capacity
was 0.088 MW and the largest was 240 MW. The fuels that are commonly used in a CPP
include lignite, coal, fuel oil, light diesel oil, high speed diesel, naptha, natural gas, and
bagasse (fibers left from sugarcane). Cement industries are typical consumers of coal,
58


gas, and naptha and the typical sizes of the CPPs are medium (30 MW capacity) to large
(above 50 MW capacity) (Shukla et al., 2004; Ambuja Cements Ltd, 2010). Many
industries that use CPPs use the plants as backups, but within the cement industry the
CPPs provide the main advantage of a reduced cost in generation compared to tariffs
established for industries by state utilities (Shuklaet al.2004). Between 2009 and 2010
59% of cement production in India was achieved with captive power plants.
Another method of reducing energy demand within the cement manufacturing
process is to use the method of waste heat recovery. Waste heat recovery leads to a
reduction in fuel consumption which in turn could reduce the size requirements for the
equipment needed for the waste heat recovery system and reduce emissions from
combustion of fuels. Waste heat recovery systems in cement plants utilize hot gases for
electricity production (also known as co-generation) or it can be used for preheating the
raw material. Most waste heat from dry process cement kilns are within a temperature
range of 620-730C (1148-1346F) which is considered a medium temperature range
(230-650C [450-1200F]) for waste heat recovery (BCS Incorporated, 2008).
Preheating is the most common form of waste heat recovery and is accomplished by
absorbing the waste heat from kilns and transferring the heat to the raw meal through 6 to
4-stage cyclones that are located before the kiln (Refer to Figure 3.4).
The efficiency of power generation depends on the temperature of the waste heat.
Thus traditional waste heat recovery technologies need medium to high temperatures to
produce power. To power an electric generator from waste heat, this can involve heating
boilers to generate steam that turns a turbine. For cement kilns other technologies
besides the traditional waste heat to boilers are being explored. These technologies
59


include organic Rankine and Kalina cycles. These technologies are being considered
because they work more efficiently even with low to medium gas exhaust temperatures.
The organic Rankine cycle uses an organic fluid (i.e. silicon oil, propane, isobutene, etc.)
instead of steam with a higher molecular mass (desired for compact designs) and high
mass flow to turn a turbine which will generate electricity. The Kalina cycle is similar to
the Rankine cycle except it involves the use of ammonia and water as the working fluid.
The combined use of fluids is called a binary fluid. Binary fluids can achieve greater
efficiency because the boiling points of ammonia and water are different, therefore
concentrations can be varied to attain more specific temperatures. Also, standard steam
turbine components can be used if ammonia and water are used in a waste heat recovery
system because both molecular weights (ammonia =17.03 and water =18.01) similar to
steam so standard steam turbine components can be used in the waste heat recovery
system (Mirolli, 2005; BCS Incorporated, 2008).
Figure 3.6 Cyclone Heat Exchangers and Precalciner (Gani, 1997)
60


Use of by products and/or waste as fuels reduces the cement industries demand
for virgin fossil fuels and can reduce the industrys C2 emissions. Hazardous and non-
hazardous materials are sources of energy and can be used for fuel in cement kilns. The
practice of using waste and by-products from other industries to create a closed-loop for
resource use is also known as waste co-processing. This practice has been common
among cement manufacturing industries in some parts of the world for more than 20
years and is considered a method for waste management (i.e. Norway) (WBCSD2005b).
To encourage safe and sustainable use of waste materials the Cement Sustainability
Initiative established by the World Business Council for Sustainable Development has
developed a document that provides guidance on the selection of fuels and raw materials
for the cement manufacturing process (WBCSD2005b). Types of alternative fuels are
listed in Table 3.7. However, the selection process for using alternative fuels depends on
certain parameters, besides health, safety, and environmental considerations, which must
be evaluated. For example, the assessment should be based on chlorine, sulfur, and alkali
content (these constituents can clog the kiln system), water content, heat value, and ash
content (ash content affects the chemical composition of the clinker). Any by-product or
waste material must be introduced at the correct point in the cement manufacturing
process in order to avoid unwanted emissions or changes in the necessary chemical
composition of the clinker (WBCSD, 2005b).
61


Table 3.7 Examples of Non-Hazardous and Hazardous Alternative Fuels
Alternative Fuels
Meat, bone meal, animal fat
Tires
Plastics
Paper/wood/cardboard
Coal slunies/distillation residues
Sludge (sewage, water purification)
Oil shales
Agriculture, organic waste
Paint residue
Packaging waste
Waste oil, oiled water
Solvents
(WBCSD2005b)
3.6 Management, Energy Efficiency Ventures, and Emission Trends for Indian
Cement Companies
Understanding how the companies are managed can also explain why the Indian
cement industry consumes less energy and still be able to produce more cement per year
in comparison to a country like the U.S. (where Table 3.6 shows the differences in
cement production). Periodicallycement companies in India will restructure and
consolidate. For example, Gujarat Ambuja Cements Ltd. has a 14% stake in ACC
Limited, Grasim Industries Limited acquired controlling stake over UltraTech in 2004,
then Grasim vested with Sammddhi Cement in 2010 and finally merged with UltraTech
(UltraTech, 2012; Dutta & Mukherjee, 2010). Additionally, the Indian cement industry
comprises of some overseas investors. Stakes in Indian cement companies have been
acquired by multinational companies such as Lafarge (acquired TISCOs operation) and
Holcim (entered with Gujarat Ambuja) (Dutta & Mukheijee, 2010). Advantages of
merging and reorganization of cement companies in India have evolved into the
following: opportunity for the company to be highly competitive, have access to new
62


markets, and pursue cost effective and energy efficient technologies (Dutta & Mukherjee,
2010).
3.6.1 Energy Efficiency and Embodied in Cement Manufacturing in India
The Cement Manufacturers Association (2010a) from 2006 through 2010
indicated that companies collaborated with the State Pollution Control Board and GTZ
German Technology Corporation on trials of using waste derived fuels. The results of
such collaboration led to recommendations for recycling hazardous wastes such as tires,
paint sludge, petroleum tar waste, and effluent treatment plant sludge in the cement kiln.
Cement companies such as Ambuja Cements received awards (such as the 2010 Green
Tech Gold Environment Excellence Award and the 2010 National Award for Excellence
in Water Management Award) emphasizing the companys investment in energy efficient
technologies. Ambuja has also indicated that 70% of total power requirement in 2011 was
generated from the captive power plants. An article in The Hindu Business Line
indicated that a 1 million tonne cement plant would need about a 20 MW of power
capacity and according to the Grasim Sustainability Report a combined capacity of 144
MW captive power plants are located at four sites. So it might be assumed that on-site
captive power plant capacity could range between 1 MW to 40 MW depending on the
capacity of cement production (Ramakrishnan2012 & Grasim Industries Ltd.2008).
India Cements Company has an 8 MW waste heat recovery plant. ACC Ltd. Cement
Company uses captive power to meet 72% of its power requirement (Ramakrishnan
2012). Grasim Industries began utilizing hazardous waste in kilns since 2007-2008 and
reported that 1,400 tonnes of coal was replaced with 2,823 tonnes of hazardous waste
between 2007 and 2008. Grasim has setup a municipal solid waste processing plant such
63


that the processed waste used as alternative fuel in 2007 was 7126 tonnes. Between 2007
and 2008 Grasim received the Energy Conservation Award and the Greentech Silver
Award for reductions in dust emissions. Grasim was one of the earliest users of the
rankine cycle technology for waste heat recovery (Grasim Industries Limited, 2008).
Within the annual reports prepared by the individual companies information about how
the company conserved energy or upgraded equipment within plants is reported.
Understanding technological upgrade and methods of generating energy and fuel
use within the Indian cement industry was important for this study in order to verify or
calculate a cement emission factor. As will be explained in the section pertaining to the
life cycle analysis (LCA) of cement a cement emission factor had been calculated by a
few organizations or entities within the country of India, however, these emission factors
did not agree with one another. Therefore, as part of this study it became pertinent to
perform a bottom-up approach to calculate or verify the Indian cement emission factor
which required a little more in-depth knowledge about individual companies. Since, the
case study involved the city of Rajkot the Indian cement companies that were located in
Gujarat were used for the performance of the LCA.
According to the CMA (2010c) between 2009 and 2010 there were at least eight
different member companies that had plants in the state of Gujarat. Three of the member
companies (Gujarat Sidhee Cement, Saurashtra Cement [known as the brand Hathi] and
Ultratech Cement Ltd.) and two non-member companies (Grasim Industries and Ambuja
Cements Ltd.) were chosen for the LCA study.
64


3.6.2 Emission Trends in Cement Manufacturing in India
GHG emissions have been associated with the charge of contributing to climate
change. As stated previously the importance of quantifying these emissions leads to
comprehension of material use and embodied energy of these materials. Finally, methods
for reducing emissions depend on revolutionizing the way materials are used and
modifying the embodied energy associated with the materials. Total emissions can be
calculated by multiplying an emission factor (EF) by the total amount of activity or
production of a material. The EF or emission intensity is the rate of a pollutant or gas
relative to the activity or production of material (IPCC, 1996).
The C2 emissions from the production of cement are a function of two
processes: calcining and the combustion of fuel. Calcining is the process when the raw
material chemically changes when reaching extremely hot temperatures. In other words
when heating the calcium carbonate (CaC3)coming from calcium rich materials (i.e.
limestone)calcium oxide (CaO) and carbon dioxide (C2) form (see also Equation 3.1)
CaC03 + Heat CaO + C02 (3.1)
Estimation of C2 emissions from calcining is a function of the lime (CaO) percentage
(content) for clinker. In the IPCC 1996 guidelines the default lime content was
estimated at 0.646. Lime percentages vary little between cement plants so if lime content
is unknown the IPCC default factor is often used (WBCSD, 2005a). Lime content can
result from other materials such as fly ash and not from the calcium carbonate. If that is
the case this percentage of lime content should be subtracted out of the total lime content
before calculating the calcining emission factor (IPCC2006). The lime content is
multiplied by the molecular weight ratio for C2/CaO (44.01 g/mole + 56.08 g/mole =
65


0.785) to calculate tonnes of CCVtonne of clinker. Thus the emission factor (EF) for
calciningin reference to clinker producedis 0.507 tonnes CCVtonne of clinker (IPCC
1996). In the 2006 IPCC guidelines a correction factor for cement kiln dust (CKD) was
incorporated into the calcining emission factor. C2 can result from lost CKD and can
range between 1.5 and 20% for a cement plant. If no information is available on CKD
the default factor recommended by IPCC (2006)is 1.02. The 0.507 tonnes CCVtonne of
clinker factor is multiplied by the CKD correction factor (See Equation 3.2. The
corrected calcining emission factor is 0.517 tonnes CCVtonne of clinker.
EFciinker = time content xmolecular weight of CO 2,CaO xCKD correction factor
EFcUnker = 0.646 x . 785 x L 02
EFciinker = 0.517 tonnes CO 2/tonne of clinker (3.2)
The general methodology for estimating emissions from the combustion of fuel
and electricity used requires the knowledge of the total amount of fuel or energy used in
the process, and the emission factor that relates the rate of CO2 released per amount of
fuel combusted or electricity used. The amount of fuel used in the process can be
reported as total volume, mass, or energy. Additionally, the emission factor can be
reported as rate of CO2 released relative to energy associated with the fuel combusted. In
these cases the calorific value (i.e. kcal/ kg) and density of the fuel (kg/m3) is needed in
order to derive a final emissions factor in the form of tonnes of CO2 per tonne of cement
produced.
This study involves the calculation of an emission factor for cement, but the
government of Indiathe Cement Manufacturers Associationas well as a few individual
cement companies have established cement emission factors. However, recent (years
66


Sources: A Schumacher, Sathaye, 1999; B Hendricks, Worell,de Jager, Blok,
Riemer, 2004; C Parikh, Sharma, Kumar, Vimal, IRADe, 2009; D CCAP, TERI,
2006; E GargShuklaKaphse2006; F MoEF2010; G CMA2010a; H
WBCSD2010
Figure 3.7 Indian Cement Emission Factors for 1991-2010
Emission factors reported in 2006 and 2007 were a result of the CMA taking part
in a two phase project, under the Ministry of Environment (MoEF) and Forests and
United Nations Framework Convention on Climate Change (UNFCCC), titled NATCOM
(National Communication). The project involved annualizing GHG emissions for
developing countries who were participants in the Kyoto Protocol. The CMA gathered
data to calculate emissions from 119 major plants out of 136 in 2007 (this was
67
2007-2010) emission factorseven if for the same yearvary between 0.65 0.83 tonne
C2/tonne of cement material (Refer to Figure 3.7). From Figure 3.7 there is a
downward trend in emissions starting from 1996 to 2010. The decrease in emissions is
best explained by the upgrade of equipment for energy efficiency, the use of captive
power, cogeneration, clinker substitution (with raw materials such as fly ash and slag),
and wind power generation (CMA2010a).
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approximately a 88% response to a questionnaire of questions sent out to the companies).
During the process for gathering data for emissions, the CMA encountered certain
problems. For example, many of the major companies (their capacity accounted for 40%
of the total capacity of the country) were not CMA members and had chosen to report
emissions using the system affiliated with the Cement Sustainability Initiative established
by the World Business Council on Sustainable Development. These companies included
Grasim Industries [now under UltraTech], ACC Ltd., and Ambuja Cements Ltd. In
Figure 3.7 for the years 2007 through 2010, individual cement companies had
volunteered to report company emissions through the Cement Sustainability Initiative
(CSI), Both CMA and CSI follow IPCC guidelines; however, according to the CMA
there are some differences between CMA and CSI in their process for emissions
calculations which were not explained. Upon review of the guidelines by CSI the
differences could lie in the emissions factors for the fuels. CSIs guidelines are meant for
use by many companies around the world so only default emission factors listed in IPCC
and a few CSI calculated emission factors are listed in the guidelines. It is possible the
cement companies in India who are working under the CSI protocol may have not used
country specific emission factors for fuel as has been done by the MoEF and CMA. A
list of fuel and electricity emission factors is shown in the Appendix as Taole B.1.The
purpose of Table B.1 is to show users how important it is to research the correct fuel
emission factor because often a fuel may be called something different between countries
but is essentially the same fuel or sometimes the fuel emission factor can be updated
every few years. Additionally, in order to create Table B.l it involved an intensive
literature review. At the time of the study there was not a well established database of
68


country specific emission factors. Current comprehensive online emission factor
databases or up-to-date life cycle inventory data are not free and require the user to pay a
certain fee. Such databases include http://www.ecoinvent.org/ and
http://emissionfactors.com/
Calcining emission factors can differ and Table 3.8 shows some examples. CSI
provides guidance to companies on how to calculate C2 emissions from calcination of
clinker, dust, and carbon from raw materials. The guidelines specifically encourage
companies to measure calcium Oxide (CaO) and magnesium oxide MgO contents of
clinker at the plant level (WBCSD, 2005a). These measurements can give a more precise
emission factor for calcination and will most likely differ from IPCCs default 0.517
tonnes CCVtonne of clinker. Grasim, in their 2007-2008 sustainability report, calculated
a calcining emissions factor that differed from IPCCs default by about 20/. The CMA
also calculated their own calcining emission factor (which includes a CKD factor) as
0.537 tonnes C2/tonnes clinker produced. The values reported by GRASIM and
MoEF/CMA could be representative of a range of Indias calcining emission factors. For
this study it was decided that CMA5s calcining emission factor of 0.537 tonnes
C02/tonne of clinker would be used in the life cycle analysis.
Table 3.8 Example Differences in Calcining Emission Coefficients
Source Year Calcining emissions (tonne C02/tonne of clinker)
MoEF/CMA 2010 0.537
GRASIMAVBCSD 2008, 2010 0.555
IPCC 1996, 2006 0.517
Note: Grasim actually reported a calcining emission factor of 0.427 tonnes CCh/tonne of
cement. The Grasim sustainability report, however, did not show total clinker produced,
69


thus a cement/clinker ratio was assumed based on the industry average for the year
2007-2008 in order to convert to tonne CO 2/tonne of clinker. The industry average for
cement/clinker ratio was 1.45 and for a company like UltraTech (who merged with
Grasim) its ratio was 1.14. So the average between the two ratios (1.3) was used in
order to calculate calcining emissions for Grasim (Source:
http://content.icicidirect.com/mailimages/Ultra tech-final.pdf)
3.7 Materials, Fuels, and Emissions Associated with Cement and Concrete
3.7.1 Cement
Based on CMA5s cement emission factor and the emission factors reported by
individual companies through the CSI it was uncertain which was most representative of
the Indian cement industry. Observations of cement use in Rajkot led to the decision to
determine a cement emission factor based on frequently used brands of cement in Rajkot.
The brands included Ambuja Cement Ltd., UltraTech Cement Limited, uujarat Sidhee
Cement Limited, Hathi Cement (brand name under flagship company Saurashtra Cement
Limited). Using the annual reports published through company websitesa years worth
of data was gathered either for 2009-2010 or 2010-2011 regarding the electricity
purchased, total energy used from coal, total volume of certain fuels and oils, total clinker
produced, and total cement produced. Typical data gathered from the annual reports are
shown in Figure B.1 in Appendix B. The annual reports provided the opportunity to
determine which companies were taking advantage of certain technologies (as discussed
in Section 3.4.2) that made the manufacturing process more energy efficient. Table 3.9
lists all the raw data gathered from the four companies. The clinker/cement ratio was
calculated from the production of cement and clinker that was reported on the annual
reports. From Table 3.9 it is important to note that all companies reduced the dependence
on grid electricity through the use of captive power plants. Major companies such as
UltraTech showed the use of waste heat recovery.
70


Table 3.9 Fuel and Electricity Raw Data Gathered for Calculation of Cement Emission Factor
2009-2010, 2010-2011 Data Ambuja Cements Ultra Tech Sidhee Cements Hathi Cements Average
Electricity Purchased (Kwh) 402000000 361072000 108177000 1079000 218082000
Total Rs. 1696900000 1812100000 676616000 15148000 1050191000
Rate (RS/Unit (Kwh)) 4.22 5.02 6.25 5.68 5.29
Electricity Generated (Kwh) 186400000 61264000 167000 1259000 62272500
NetUnits/Ltr. Of Light Diesel Oil/Fumace oil 3.9 3.93 3.13 3.65
LDO/fumace oil cost (Rs)/Unit Generated 7.02 6.99 8.77 7.59
Fuelcost/electricity duty 16.04 16.04
Electricity Steam Generator (Kwh) 1209300000 1187204000 132248000 842917333
Net Units / T of Fuel 842 1030 936
Oil/Gas Cost/unit 3.14 3.17 3.85 3.39
Total Amount (Rs) 508910000
Waste Heat Recoveiy System (kWh) 13997000 13997000
Cost/Unit 0.4 0.4
Coal (million K Cal) 10533678 18410858.27 937363 1026672 7727142.82
Cost (Rs.) 8930000000 10861700000 970970000 1033487000 5449039250
Average Rate (Rs/millionK. Cal) 847.53 589.96 1035.85 1006.64 870.00
Light Diesel Oil/High Speed Diesel(K liters) 3508.87 1112.00 184.79 1601.89
Cost (Rs.) 126900000 39900000 7563000 58121000
Average Rate (Rs/K. liters) 36178 35903 40926.35 37669.12
Furnace Oil (Including Naphtha) (K liters) 22692 682 11687
Cost (Rs.) 488500000 16662000 252581000
Average Rate (Rs/K. liters) 21527 24431 22979.04
High Speed Diesel Oil (HSD) (K liters) 3154 3154
Cost (Rs.) 110000000 110000000
Average Rate (Rs/K. liters) 34861 34861
LDO (Liter)/Tonne of clinker 0.24 0.11 0.16 0.17
Coal and other fuels (K. Cal/Kg. of Clinker) 750 709 811 802 767.93
Electricity (Kwh/Tome of cement) 85.9 83.13 86.21 102.85 89.52
Total Cement Production (tonnes) 20100000 17639000 1211754 1158720 10027368.5
Clinker sold 343525 2461000 29725 202231 759120.25
Clinker Produced (tonnes) 14100000 15550000 1160000 1280610 8022652.5
Ratio (clinker/cement) 0.70 0.88 0.96 1.11 0.91


The electricity and fuel data was converted to total C2 emissions using country
specific emission factors available from various sources listed in Table 3.10. As seen in
Table 3.9 not all the fuel information was recorded in terms of energy. For the fuels that
were recorded in units of volume, information such as calorific value of the fuel and
density of the fuel were required. The calorific values are included in Table 3.10 and
density values are shown in Table 3.11. An average density was calculated within each
range shown in Table 3.11 and was used in the calculations for total CO2 from the fuel
used. The equations below are shown to clarify the process used to determine the unit
mass of CO2 from total fuel used in the cement manufacturing process for the year. Note:
All fuel for on-site transportation was assumed to be included in the data provided in the
annual reports. If transportation energy use was not reported as part of the annual
reports then according to the study performed by MarceauNisbetand VanGeem (2010)
we can assume transportation energy contributes about 2% of total energy input.
Marceau, Nisbetand VanGeem calculated an average of 0.09 IGJ/tonne of cement
(39. IBtu/lb cement) and 3.2 kgCCh/tonne of cement (6.41 lb of CO 2/ton of cement) from
transportation.
total mass of fuel = total liters of fuel x density
total energy of fuel = total mass of fuel x calorfic value
unit mass of C02
unit mass of C02 = total energy from fuel x
unit energy of fuel
or
unit mass of C02
unit mass of C02 = total mass of fuel x---------------~-
unit mass of fuel
72


Table 3.10 Country Specific Emission Factors Used in Calculating a Cement
Emission Factor
Fuel/Electricity kg C02/kWh Source and Additional Information
Electricity Coal
Purchased
Coal
0.83
0.35
CEA, 2009
The value was the average of coking, non-
coking, and Kgnite which is the usual
Indian coal &el mix. An average was
taken from the following Indian EF:
93.6195.81106.15 tonnes C02/TJ
(MoEF, 2010)
Light Diesel Oil 0.26 Both the NCV and EF were used to calculate the EF in terms of C02 per energy. The Indian EF = 3.18 tonnes C02/tonne and NCV = 43.33 TJ/kilotonnes (Ramachandra and Shwetmala, 2009)
Furnace oil is also called &el oil. The Furnace oil 0.28 Indian EF = 77.4 tonnes C02/TJ
High Speed Diesel Oil 0.26 Both the NCV and EF were used to calculate the EF in terms of C02 per energy. The Indian EF = 3.18 tonnes C02/tonne and NCV = 43.33 TJ/kilotonnes (Ramachandra and Shwetmala, 2009)
Natural Gas
0.20
CCAP & TERI, 2006 EF actually
reported as 55.82 tonnes ofC02/TJ
1 kg C02/kWh = 646 lb/MBtu
Table 3.11 Density Values for Certain Fuels Used in Indian Cement Manufacturing
Fuel/O0
Dens
Diesel Oil
820-880
Furnace Oil
890-950
High Speed Diesel Oil_ 820-860
Source
Indian Oil Corporation Ltd
(http y/www. iocl. com/)
Bureau of Energy Efticiency
Fuels and Combustion
Guidelines (www.em-ea.org)
Indian Oil Corporation Ltd
(http y/www. iocl. com/)
1 kg/m = 0.062 lb/in
73


Tables 3.12 through 3.19 demonstrate how the energy reported in the annual reports were
converted into total emissions. Energy is considered the material flow analysis portion
while the emissions factor for each type of fuel used for energy is conisdered the life
cycle analysis results. Finally MFA multiplied by LCA results into total impact or total
emissions from the energy produced from the fuel.
Table 3.12 MFA-LCA Data for Purchased Electricity
Purchased Electricity
Company MFA LCA Total Emissions
(kWh) (kgC02/kWh) (kgCO
Ambija F 4.02E+08 0.83 3.E+08
UltraTech r 3.61E+08 0.83 3.E+08
Sidhee r 1.08E+08 0.83 9.E+07
Hathi 1.08E+06 0.83 9.E+05
Table 3.13 MFA-LCA Data for Company Generated Electricity from Coal
Generation Electricity (Coal)
Company MFA (kWh) LCA (kgC02/kWh) Total Emissions (kgC02)
Ambija F 0.00E+00 0.60 0.00E+00
UltraTech r 1.19E+09 0.60 7.16E+08
Sidhee r 0.00E+00 0.60 0.00E+00
Hathi 1.32E+08 0.60 7.97E+07 ^
Table 3.14 MFA-LCA Data for Company Generated Electricity from LDO/Furnace
Oil
Own Generation Electricity (LDO/Furnace OU)
Company MFA (kWh) LCA (kgC02/kWh) Total Emissions (kgC02)
Ambiia r 1.86E+08 0.46 8.50E+07
UltraTech r 0.00E+00 0.46 0.00E+00
Sidhee r 1.67E+05 0.46 7.62E+04
Hathi r 1.26E+06 0.46 5.74E+05 ^
74


Table 3.15 MFA-LCA Data for Company Generated Electricity from Natural Gas
Generation Electricity (Natural Gas)
Company MFA (kWh) LCA (kgC02/kWh) Total Emissions (kgC02)
Ambiia r 1.21E+09 0.32 3.9E+08
UltraTech r 6.13E+07 0.32 2.0E+07
Sidhee r 0.00E+00 0.32 0.0E+00
Hathi r 0.00E+00 0.32 0.0E+00 J
Table 3.16 MFA-LCA Data for Thermal Energy from Coal
Thermal Energy (Coal)
Company MFA (kWh) LCA (kgC02/kWh) Total Emissions (kgC02)
Ambiia r 1.22E+10 0.35 4.3E+09
UltraTech r 1.34E+10 0.35 4.8E+09
Sidhee r 1.09E+09 0.35 3.9E+08
Hathi r 1.19E+09 0.35 4.2E+08 J
Table 3.17 MFA-LCA Data for Thermal Energy from Light Diesel
Thermal Energy (Light Diesel)
Company MFA (kWh) LCA (kgC02/kWh) Total Emissions (kgC02)
Ambiia r 3.71E+07 0.35 1.3E+07
UltraTech r 1.18E+07 0.35 4.2E+06
Sidhee r 1.95E+06 0.35 6.9E+05
Hathi r 0.00E+00 0.35 0.0E+00 J
Table 3.18 MFA-LCA Data for Thermal Energy from Furnace Oil
Thermal Energy (Furnace OU)
Company MFA (kWh) LCA (kgC02/kWh) Total Emissions (kgC02)
Ambiia r 0.00E+00 0.28 0.0E+00
UltraTech r 2.55E+08 0.28 7.1E+07
Sidhee r 0.00E+00 0.28 0.0E+00
Hathi r 7.66E+06 0.28 2.1E+06 J
75


Table 3.19 MFA-LCA Data for Thermal Energy from High Speed Diesel Oil
Thermal Energy (High Speed Diesel OU)
Company MFA (kWh) LCA (kgC02/kWh) Total Emissions (kgC02)
Ambiia r 0.00E+00 0.26 0.0E+00
UltraTech r 3.19E+07 0.26 8.4E+06
Sidhee r 0.00E+00 0.26 0.0E+00
Hathi r 0.00E+00 0.26 0.0E+00 J
Table 3.20 shows the total production of cement for a given year for each company.
Table 3.20 Cement Production from Major Cement Manufacturing Companies that
Deliver to Rajkot, India_________________________________
Cement Production Ambuja UltraTech Sidhee Hathi
Cement (million tomes cement) 20.10 17.64 1.21 1.16
3.7.1.1 Overall Result
Table 3.21 and Table 3.22 show the results of energy use and C2 emissions
arising from the fuels and electricity per unit production of cement. The calculations were
based on four major cement companies that have plants located in Gujarat and provide
cement to city projects based in Rajkot, India. From Tables 3.9 and 3.22, the data
revealed that Ambuj a and UltraTech are the larger producers of cement and total C2
emissions. All companies do use captive power plants to save on costs spent on
purchased electricity either by generating electricity through fuel oils and coal (Refer to
Table 3.9). Companies such as Ambuj a and UltraTech appear to be using natural gas as
well (Ambuja, 2010; UltraTech, 2011; and Shukla et al., 2004). UltraTech in particular
reported some energy savings through the use of waste heat recovery. The savings
totaled about 0.002GJ/tonne of cement (1.2 Btu/lb of cement). Finally, averaging the
four main Gujarat cement producing companies revealed that the average cement
emission factor is approximately 0.84 tonnes C2/tonne of cement (1680 lb C2/short
76


Full Text

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ANALYZING ENVIRONMENT A L AND STRUCTURAL CHARACTERSITICS OF CONCRETE FOR CARBON MITIGATION AND CLIMATE ADAPTATION IN URBAN AREAS: A CASE STUDY IN RAJKOT, INDIA by Andrea Valdez Solis B.S., New Mexico State University, 2006 M.S. New Mexico State University, 2008 A dissertation submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirements for the degree of Doctor of Philosop hy Civil Engineering 2013

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2013 ANDREA VALDEZ SOLIS ALL RIGHTS RESERVED

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ii This dissertation for the Doctor of Philosophy degree by Andrea Valdez Solis has been approved for the Civil Engineering Program by Stephan A. Durham, Chair Anu Ramaswami Co Advisor Arunprakash Karunanithi Ross Corotis Yunping Xi December 17, 2012

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iii Solis, Andrea, Valdez (Ph.D., Civil Engineering) Analyzing Environmental and Structural Charact eristics of Concrete for Carbon Mitigation and Climate Adaptation in Urban Areas: A Case Study in Rajkot, India Dissertation directed by Associate Professor Stephan A. Durham ABSTRACT Increasing temperatures, varying rain events accompanied with flooding or droughts coupled with increasing water demands, and decreasing air quality are just some examples of stresses that urban systems face with the onset of climate change and rapid urbanization. Li terature suggests that greenhouse gases are a leading cause of climate change and are of a result of anthropogenic activities such as infrastructure dev elopment I nfrastructure development is heavily dependent on the pr oduction of concrete. Yet, concrete can contribute up to 7% of total CO 2 emissions g lobally from cement manufacturing alone T he goal of this dissertation was to evaluate current concrete technologies that could contribute to carbon mitigation and climate adaptation in cities. The objectives used to reach the goal of the study included (1) applying a material flow and life cycle analysis ( MFA LCA ) to determine the environm ental impacts of pervious and high volume fly ash ( HVFA ) concrete compared to ordinary portland cement ( OPC ) concrete in a developing country; (2) performing a comparative assessment of pervious concrete mixture designs for structural and environmental ben efits across the U.S. and India; and (3) Determining structural and durability benefits from HVFA concrete mixtures when subjected to extreme hot weather conditions (a likely element of climate change)

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iv The study revealed that cities have a choice in re ducing emissions, improving stormwater issues, and developing infrastructure that can sustain higher temperatures. Pervious and HVFA concrete mixtures reduce emissions by 21% and 47%, respectively, compared to OPC mixtures. A pervious concrete demonstrat ion in Rajkot, India showed improvements in water quality (i.e. lower levels of nitrogen by as much as 68% fr om initial readings), and a reduction in material costs by 25% HVFA and OPC concrete mixtures maintained compressive strengths above a design s trength of 27.6 MPa (4000 psi), achieve d ed changes in length that could be detrimental to the performance of the concrete in long term temperatures above 37.8 o C (100 o F) The form and content of this abstract are approved. I recommend its publication. Approve d: Stephan A. Durham

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v DEDICATION I dedicate this work to my parents Loretta Valdez and Andrew Chvez and to all the people from the pueblitos of Northern New Mexico. The love, care, and support these people show help others strive for the best, believe, and remain positive in life.

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vi ACKNOWLEDGEMENTS I would like to thank my advisors Dr. Stephan Durham and Dr. Anu Ramaswami My advisors provided me a unique PhD experience that has taught me how to be a stronger person both in life and in my profession. The PhD was challenging but, Dr. Duhram and Dr. ramswami helped me to realize the importance of remaining patient, motivat ed, and grateful while doing research. I am honored to have studied under the guidance of these two very important people who are admired for their personalities and contributions to engineering and sustainability. I come away with a PhD striving to mode l the best attributes of my advisors, Dr. Durham for his practicality, passion for teaching, and appreciation he shows to others and Dr. Ramswami for her devotion and dedication she puts into every project, ability to challenge and motivate you with her wo rds, and the courage they both display in being leaders in research. I would like to emphasize that the PhD experience was feasible and memorable times spent drinking tea, talking to and joking with fellow students and staff, or learning about cultures and collaborating with people across the world I would have overlooked how exceptional and distinct each person is in this world. It so important to learn how to work wi th different people and appreciate that chance to listen to their ideas, knowledge, concerns, and joys. I want to thank Tom Thuis, Randy Ray, Dr. Nien Yin Chang, Dr. Kevin Rens, Dr. Rajaram, Jose Solis, Adam Kardos, Dr. Loren Cobb, Dr. Angie Hager, Derek Chan, Dr. Rui, Liu, Devon, Krista Nordback, Brian Volmer for all their help during my research and dissertation preparation. I thank Laasya Bhagavatula, Emani Kumar, Ashish Rao Ghorpade of ICLEI South Asia, Mr. Jayant Lakhlani of Lakhlani

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vii Associates, Mite sh Joshi and his family and Alpana Mitra and her family for making me feel welcomed in Rajkot, India and giving me the honor of working with all of you while doing the research in Rajkot. Additionally, I appreciate the feedback and commitment that my comm ittee members (Dr. Ross Corotis, Dr. Arunprakash Karunanithi, and Dr. Yunping Xi) showed during defense. I would also like to thank the Nation al Science No. DGE 0654378 ) for funding my research. Lastly, I thank my family, friends, and especially my parents. It is hard to explain how much I appreciate the qualities of my parents because my parents mean a lot to me and I want to say the right words. My mom is always forgi ving, a great listener, and I admire her for her ability to manage people and make people feel important. My dad is a very intelligent man that enjoys the simple things in life (like working side by side with his children), he gives valuable advice and I admire him for how hard he works. I am able to achieve any goal because my parents have always been there pushing me along, keeping me focused, and making me believe I have a purpose.

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viii TABLE OF CONTENTS Chapter 1. Introduction ................................ ................................ ................................ ...................... 1 1.1 Concrete and Urban Infrastructure ................................ ................................ ................. 1 1.1.1 Concrete Use ................................ ................................ ................................ .............. 1 1.1.2 Concrete Infrastructure Is a Source of GHG Emissions ................................ ............ 3 1.2 Climate Change in Urban Areas ................................ ................................ .................... 3 1.2.1 Flooding or Drought in Urban Areas ................................ ................................ .......... 4 1.2.2 Extreme Temperatures in Urban Areas ................................ ................................ ....... 5 1.3 Concrete Infrastructure for GHG Mitigation and Climate Adaptation .......................... 6 1.3.1 Pervious Concrete Past and Contemporary Research ................................ ................ 7 1.3.2 High Volume Fly Ash Concrete Research with a Focus on Thermal Properties ...... 9 1.3.3 Main Goal and Knowledge Gaps ................................ ................................ .............. 13 1.4 Thesis Objectives ................................ ................................ ................................ ......... 16 1.5 Organization of Thesis ................................ ................................ ................................ 17 2. Case Study Location: The City o f Rajkot India ................................ ............................. 19 2.1 Demographics, Population, and Climate ................................ ................................ ..... 19 2.2 Rajkot Construction and Concrete Infrastructure ................................ ....................... 21 2.2.1 Personal A ccount of Construction ................................ ................................ ........... 22 2.2.2 Rajkot Concrete Infrastructure ................................ ................................ .................. 25 2.3 Future GHG Mitigation and Climate Adaptation Goals ................................ .............. 29 2.3.1 Stormwater/Rainwater Harvesting ................................ ................................ ............ 31 2.3.2 HVFA Concrete Road Project ................................ ................................ .................. 32

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ix 2.3.3 Collaboration between UC Denver, ICLEI South Asi a and Rajkot Municipal Corporation ................................ ................................ .......... 34 3. Carbon Mitigation Through Concrete: An MFA LCA Approach ................................ 36 3.1 Bottom line: Cement and Concrete Manufacturing in India and the US ..................... 36 3.2 Life Cycle Assessment of Cement and Concrete in India ................................ .......... 41 3.3 Understanding the Cement Production and Concrete Industry in India ..................... 44 3 .3. 1 Ready Mixed Concrete Industry in India ................................ ................................ .. 48 3.3.2 Site Mixed Concrete in India ................................ ................................ ................... 49 3.3.3 Indian Concrete Mixture Designs ................................ ................................ ............ 51 3.4 Cement Manufacturing Process in India ................................ ................................ ..... 52 3.4.1 Phases of Cement Clinker ................................ ................................ ........................ 54 3.4.2 Kilns ................................ ................................ ................................ ......................... 55 3.5 Energy Consumption within the Cement Industry ................................ ...................... 56 3.5.1 Energy Scenario in the Indian Cement Industry ................................ ...................... 57 3.5.2 Methods of Energy Efficiency ................................ ................................ ................. 58 3.6 Management, Energy Efficiency Ventures, and Emission Trends for Indian Cement Companies ................................ ................. 62 3.6.1 Energy Efficiency and Embodied in Cement Manufacturing in India .................... 63 3.6.2 Emission Trends in Cement Manufacturing in India ................................ ............... 65 3.7 Materials, Fuels, and Emissions Associated with Cement and Concrete ................... 70 3.7 .1 Cement ................................ ................................ ................................ ..................... 70 3.7 1.1 Overall Result ................................ ................................ ................................ ....... 76 3.7.1.2 Company to Company Comparison ................................ ................................ ...... 77 3.7.1.3 Cementitious Materials ................................ ................................ ......................... 79

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x 3.7.1.4 Energy Intensity ................................ ................................ ................................ .... 80 3.7.1. 5 CO 2 Emissions Factor Conclusion ................................ ................................ ......... 81 3.7.2 Quarrying and Mining of Other Raw Materials (Excluding Limestone) ................................ ................................ ..... 82 3.7.3 Coarse and Fine Aggregate Crushing ................................ ................................ ...... 82 3.7 .4 Tranpsportation of Materials ................................ ................................ .................... 83 3.7.5 On site Mixed Concrete ................................ ................................ ........................... 84 3.7.6 Summary of Life Cycle Inventories ................................ ................................ ......... 85 3.8 MFA LCA of Cement Use in Rajkot ................................ ................................ .......... 87 3.9 MFA LCA for Concrete Mixtures in Rajkot ................................ .............................. 88 3.10 Summary ................................ ................................ ................................ ................... 90 4. Stormwater Solution Demonstration w ith Pervious Concrete: Structural a nd Environmental Tests ................................ ................................ .............. 91 4.1 Study Design and Laboratory Phase I Testing ................................ ............................ 92 4.1.1 Material Properties ................................ ................................ ................................ ... 95 4.1.2 Mixture D esign ................................ ................................ ................................ ........ 97 4.1.3 Test Methods ................................ ................................ ................................ ............ 98 4.1.4 Phase I Laboratory Results ................................ ................................ .................... 105 4.2 Providing Stormwater Management Solutions in Rajkot, India: A Perviou s Concrete System Demonstration ................................ ............................ 112 4.2.1 Introduction ................................ ................................ ................................ ............ 112 4.2. 2 Materials and Methods ................................ ................................ ........................... 116 4.2. 3 Test Methods and Results ................................ ................................ ...................... 124 4.3 Laboratory Phase II Testing (Cubes Versus Cylinders) ................................ ............ 136 4.3.1 Batching and Curing Phase II Laboratory Samples ................................ ............... 138

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xi 4.3.2 Sample Shape Effects on the C ompressive Strength of Pervious Concrete .......... 141 4.3.3 Comparing Compressive Strength Results ................................ ............................ 145 4.3.4 Discussion of Standard Deviations and Population ................................ ............... 149 4.3.5 Summary of Percent Porosity ................................ ................................ ................ 150 4.3.6 Summary of Hydraulic Conductivity ................................ ................................ ..... 151 4.4 Summary ................................ ................................ ................................ ................... 152 5. High Volume Fly Ash Concrete f or Hot Weather Conditions: Structural a nd Durability Tests ................................ ................................ ................... 155 5.1 Literature Regarding Fly Ash Use in India ................................ ............................... 155 5.1.1 Properties of Fly Ash ................................ ................................ ............................. 155 5.1.2 Fly Ash Consumption in India ................................ ................................ ............... 157 5.2 Literature on HVFA Concrete for Hot Weather Conditions ................................ ..... 159 5.3 Phase I study for HVFA in Hot Weather Conditions: India and U.S. Comparison of Fly Ash Properties (Fly Ash Used in Rajkot, Gujarat, India and Denver, Colorado, U.S.) ................................ ................................ ................................ ........................... 164 5.4 Phase II: Properties of HVFA and OPC Concrete When Subjected to Hot Weather Conditions ................................ ................................ ....... 172 5.4.1 Aggregate Temperatures ................................ ................................ ........................ 172 5.4.2 Verifying Temperatures of HVFA and OPC Concrete During Hydration ............ 175 5.5 Phase III study for HVFA in Hot Weather Conditions: Laboratory Testing of Structural and Durability Properties ................................ ................................ ......... 180 5.5.1 Compressive Strength ................................ ................................ ............................ 186 5.5.2 Modulus of Elasticity ................................ ................................ ............................. 191 5.5.3 Resistance to Rapid Chloride Ion Penetration ................................ ....................... 191 5.5.4 Length Change ................................ ................................ ................................ ....... 198 5.6 Applying a Multiple Linear Re gression Model to Determine the Significance of

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xii Testing Variables on HVFA Concrete versus OPC Concrete When Subjected to Hot Weather Conditions ..................................................................................................202 5.6.1 Background on Multiple Linear Regression ..........................................................202 5.6.2 Application of the Multiple Linear Regression Models ........................................203 5.6.3 Revision of Multiple Linear Regression Analysis with Original Data ..................211 5.7 Summary of Strength, Permeability, Length Change, and Multiple Linear Regression .................................................................................................................215 6. Conclusions and Recommendations ...........................................................................218 6.1 Conclusions ...............................................................................................................218 6.1.1 Carbon Mitigation: An MFA-LCA Approach .......................................................218 6.1.2. Climate Adaptation: Pervious Concrete ................................................................219 6.1.3 Climate Adaptation: HVFA Concrete ....................................................................220 6.2 Contributions .............................................................................................................221 6.3 Recommendations and Future Research ...................................................................222 6.3.1 MFA-LCA Recommendations ...............................................................................223 6.3.2 Pervious Concrete Recommendations ...................................................................223 6.3.3 HVFA Concrete Recommendations ......................................................................225 6.4 Final Remarks Regarding Sustainability ..................................................................235 References .......................................................................................................................236 Appendix A. .....................................................................................................................................247 B. .....................................................................................................................................253 C. .....................................................................................................................................25 D. .....................................................................................................................................258

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xiii LIST OF TABLES Table 1.1. Summary of the Benefits of Fly Ash Concrete ................................ .......................... 10 3.1 Comparison of Energy Use per Tonne of Cement Between the U.S. Cement Industry ................................ ................................ ..................... 37 3.2 Summary of Energy Use and Emission Factors from Direct and Indirect CO 2 Emissions between India and the U.S. ................................ ................................ ......... 39 3.3 World Cement Production 2010 ................................ ................................ .................. 46 3.4 Indian Cement Industry Information ................................ ................................ .......... 48 3.5 Mixture Proportions for Typical Grades of Concrete (Based on Saturated Surface Dry Conditions) ................................ ................................ .............................. 51 3.6 Average Energy Use Between India and U.S. Cement Industry for 2009 2010 ................................ ................................ ... 58 3.7 Examples of Non Hazardous and Hazardous Alternative Fuels ................................ 62 3.8 Example Differences in Calcining Emission Coefficients ................................ .......... 69 3.9 Fuel and Electricity Raw Data Gathered for Calculation of Cement Emission Factor ................................ ................................ ................................ .......................... 71 3.10 Country Specific Emiss ion Factors Used in Calculating a Cement Emission Factor ................................ ................................ ................................ ........................ 73 3.11 Density Values for Certain Fuels Used in Indian Cement Manufacturing ............... 73 3.12 MFA LCA Data for Purchased Electricity ................................ ............................... 74 3.13 MFA LCA Data for Company Generated Electricity from Coal ............................. 74 3.14 MFA LCA Data for Company Generated Electricity from LDO/Furnace Oil ................................ ................................ ............................. 74 3.15 MFA LCA Data for Company Generated Electricity from Natural Gas .................. 75 3.16 MFA LCA Data for Thermal Energy from Coal ................................ ...................... 75 3.17 MFA LCA Data for Thermal Ene rgy from Light Diesel ................................ .......... 75

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xiv 3.18 MFA LCA Data for Thermal Energy from Furnace Oil ................................ .......... 75 3.19 MFA LCA Data for Thermal Energy from High Speed Diesel Oil ......................... 76 3.20 Cement Production from Major Cement Manufacturing Companies that Deliver to Rajkot, India ................................ ................................ ............................. 76 3.21 Energy Consumption from Major Cement Manufacturing Companies that Deliver to Rajkot, India ................................ ................................ ............................. 77 3.22 Emissions from Major Cement Manufacturing Companies that Deliver to Rajkot, India ................................ ................................ ................................ .............. 79 3.23 Fl y Ash Consumption by Major Cement Companies who Deliver to Rajkot, India ................................ ................................ ................................ .......................... 80 3.24 Production and Emissions From Quarry and Mining ................................ ............... 82 3.25 Emission Factors for Aggregate Crushing ................................ ................................ 83 3.26 Emission Factors and Average Distance Travelled for Cement Transportation ................................ ................................ ........................ 83 3.27 Emission Factors and Average Distance Travelled for Transport of Aggregate ................................ ................................ ....................... 84 3.28 Emission Factors and Average Distance Travelled for Transport of Fly Ash ................................ ................................ ........................... 84 3.29 Specifications of Concrete Mixer ................................ ................................ ............. 85 3.30 Summary of Emission Factors Leading Up to Concrete Mixing .............................. 86 ............. 86 3.32 Information Regarding Rajkot Cement Use and Total Emissions per Year ................................ ................................ ................... 88 3.33 MFA Data for M35, Pervious and HVFA Concrete Mixtures ................................ .. 89 3.34 LCA Data and Total Emissions Calculations from an MFA LCA on Concrete Mixtures ................................ ................................ ................................ .................... 89 3.35 Cement Material Content and MFA LCA Emissions for Certain Concrete Mixtures ................................ ................................ ................................ .................... 90

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xv 4.1 Chemical Properties of Cement along with Standard Limits ................................ ...... 96 4.2 Physical Properties of Cement Along with Standard Limits ................................ ...... 96 4.3 Mixture Proportions for Phase I Laboratory Testing ................................ .................. 98 4.4 Porosity of Samples from Mixture 1 and Mixture 2 (Reported in Percent) ............... 105 4.5 Average Hydraulic Conductivity for Mixture 1 and 2 ................................ ............... 108 4.6a Mixutre 1 Compressive Strength Results ................................ ................................ 109 4.6b Mixture 2 Compressive Strength Results ................................ ............................... 1 10 4.7 Mixture Proportions for Rajkot ................................ ................................ ................. 120 4.8 Batch Quantities ................................ ................................ ................................ ........ 120 4.9 Specific Gravity Values Provided used in the Pervious Concrete Mixture Design ................................ ................................ ........... 120 4.10 Results of the Calculated Percentage Voids ................................ ........................... 125 4.11 Hydraulic Conductivity of the Pervious Concrete and System .............................. 126 4.12 Results of Compressive Strength of Pervious Concrete Samples ........................... 129 4.13 Water Quality Analysis of the Water from a Bore Well and Stream ...................... 131 4.14 Additional Results of Stream Water Quality Tests ................................ ................. 134 4.15 Mixture Proportions for Phase II Laboratory Testing ................................ ............. 138 4.16 Specific Gravities and Absorption Capacities in Phase II Testing ......................... 139 4.17 Compressive Strength Results for M3 ................................ ................................ ..... 145 4.18 Compressive Strength Results for M4 ................................ ................................ ..... 146 4.19 Cylinder to Cube Strength Ratio Based on Average Compressive Strengths ................................ ............................. 147 5.1 Example of Chemical Composition of Fly Ash from Different Countries (Malhotra & Mehta, 2008) ................................ ................................ ......................... 156 5.2 Year 2005 Production and Utilization of Fly Ash in India ................................ ....... 158

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xvi 5.3 Chemical Analysis for Various Fly Ash Sources between the U.S. and India ......... 165 5.4 Mixture Proportions for HVFA Concrete in Rajkot ................................ ................. 166 5.5 Compressive Strength Results for Rajkot HVFA Concrete Samples ....................... 167 5.6 Mixture Proportions for HVFA Concrete in Denver ................................ ................ 169 5.7 Fresh Concrete Properties for the HVFA Concrete Batch in Denver ....................... 169 5.8 Compressive Strength Results for U.S. HVFA Concrete Samples ........................... 170 5.9 Average Cylinder to Cube Compressive Strength Rati os for U.S. and Indian HVFA Concrete Mixtures ................................ ................................ ......................... 171 5.10 Mixture Proportioning for Mixture Designs in Phase IIa Testing of HVFA and OPC Concrete ................................ ................................ ................................ ......... 176 5.11 Mixture Proportioning for HVFA and OPC Concrete Mixture Designs in Extreme Hot Weather Condition Testing ................................ ............................... 181 5.12 ASTM Standards Used for Fresh and Hardened Concrete Tests ............................ 181 5.13 Material Temperatures Before Mixing (And During Mixing for the Heated Aggregate Mixtures) ................................ ................................ ................................ 185 5.14 Internal Peak Temperatures During Cur ing ................................ ............................ 185 5.15 Matrix for Multiple Linear Regression Analysis ................................ .................... 205 5.16 Equations of Fitted Curves from 1 st Regression Analysis ................................ ...... 206 5.17 Summary of 1 st Regression Analysis ................................ ................................ ...... 206 5.18 Equations of Fitted Curves from 2 nd Regression Analysis ................................ ..... 208 5.19 Summary of Regression Analysis When Including the TB Interaction Term ................................ ................................ ......... 208 5.20 A Comparison of Equations of Fitted Curves From 2 nd and 3rd Regression Analysis for Compressive Strength ................................ ................................ ........ 212 5.21 Comparing Significant Variables, R 2 and Standard Deviations for Compressive Strength ................................ ................................ ............................. 212 5.22 A Comparison of Equations of Fitted Curves From 2 nd and 3rd Regression

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xvii Analysis for Permeability ................................ ................................ ....................... 213 5.23 Comparing Significant Variables, R 2 and Standard Deviations for Permeability ................................ ................................ ................................ ............ 213 5.24 A Comparison of Equations of Fitted Curves from 2 nd and 3rd Regression Analysis for Length Change ................................ ................................ ................... 214 5.25 Comparing Significant Variables, R 2 and Standard Deviations for Permeability ................................ ................................ ................................ ............ 214 5.26 Summary of F Statistic and P Value from ANOVA ................................ .............. 215 6.1 Order of Performing Mixtures ................................ ................................ .................. 227 6.2 Base Mixture Design ................................ ................................ ................................ 227 6.3 Phase I Testing Summary for Each Mixture ................................ ............................. 228 6.4 Phase II Testing Summary for Each Mixture ................................ ........................... 228

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xviii LIST OF FIGURES Figure 1. 1 Concrete Consumption Forecast Compared Against Population Growth (Mehta and Monteiro, 2006) ................................ ................................ ................................ ............. 2 2.1 Location of Rajkot within the state of Gujarat, India (Google Maps) ......................... 19 2.2 Paver Blocks (a) Removal from Molds (b) Design on Surface of Blocks .................. 21 2.3 Materials Stock Piled Directly on Construction Site ................................ .................. 23 2.4 Large Scale Used for Measuring Aggregate and Cement before Batching ................. 24 2.5 Materials Transferred from Scale into Portable Diesel Powered Mixer ...................... 24 2. 6 Labore rs Placing Concrete ................................ ................................ ........................... 24 2.7 Cement Being Emptied from the Bucket and Pulley Machinery ................................ 25 2.8 Breakup of Landuse within City Limits of Rajkot (Rajkot Municipal Corporation, 2006) ................................ ................................ ................................ ............................ 26 2.9 Small Residential Buildings Near the Edge of City Limits ................................ ......... 26 2.10 Indoor Stadium ................................ ................................ ................................ ........... 2 7 2.1 1 Buildings Near the Center of the City ................................ ................................ ........ 27 2.1 2 Waste Water Treatment Plant ................................ ................................ .................... 27 2 .1 3 Construction of Housing ................................ ................................ ........................... 28 2.14 Construction of a Water Tower ................................ ................................ .................. 28 2.15 Tube Solar Water Heaters Mounted on the Roofs in Rajkot ................................ .... 30 2.16 Rajkot Municipal Corporation Office with Passive Cooling Foyer Design .............. 30 2.17 Recharging Pit or Detention Pond Park Being Cleaned ................................ ............ 31 2.18 Park Filled with Stormwater After a Rain Event ................................ ....................... 32 2.19 HVFA Concrete Road on Saurashtra University Campus (a) Two W heelers and Tractor on the Road (b) Close up of the Surface of the Road ................................ .... 33

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xix 2.20 Raiya WWTP Site (a) Placing Concrete (b) Curing Concrete ................................ ... 33 3.1 Life Cycle Phases and Material Flow for Concrete in Rajkot ................................ ..... 44 3.2 Trend in Cement Production for Four Leading Cement Producing Countries (USGS, 2012; Parikh, Sharma, Kumasr, Vimal, IRADe, 2009) ................................ ............... 47 3.3 Potential Trend in Per Capita Cement Consumption for Four Leading Cement Producing Countries (USGS, 2012; Parikh, et al, 2009; United Nations 2010b) ....... 47 3.4 Steps in cement manufacturing process at Grasim Industries Limited Cement Company (Grasim Industries Limited, 2008) ................................ .............................. 53 3.5 Phase Diagram for Ordinary Portla nd Cement (Gani, 1997) ................................ ....... 55 3.6 Cyclone Heat Exchangers and Precalciner (Gani, 1997) ................................ ............. 60 3.7 Indian Cement Emission Factors for 1991 2010 ................................ ......................... 67 3. 8 Concrete Mixer with Mechanical Hopper ................................ ................................ .... 84 4.1 Proposed Pervious Concrete System Site ................................ ................................ .... 93 4.2 Pervious Parking Lot Pavement on Auraria Campus in Denver, Colorado ................. 94 4.3 Details of the Pervious Concrete System for the Parking Lot Installation (Hager, 2009) ................................ ................................ ................................ ............................ 95 4.4 Mixture Consistency (a) Too Dry, (b) Proper Amount of Water, (c) Too Wet (Tenn is, Leming, & Akers, 2004) ................................ ................................ .............................. 99 4.5 Compressive Strength Testing (a) Using Neoprene Pads for Cylinders and (b) Steel Plates for Cubes ................................ ................................ ................................ ......... 101 4.6 Hydraulic Testing Apparatus (a) Cylinder with Stopper and Putty (b) Hole Drilled in Cylinder for Draining Water from the Cylinder into the Pervious Concrete ............. 104 4. 7 A Side by Side Comparison of the Pervious Concrete Samples ................................ 106 4.8 Average Compressive Strengths for Mixture 1 and Mixture 2 ................................ .. 110 4.9 Fracture Paths for Cylinder Pervious Concrete Samples ................................ ........... 111 4.10 Fracture Paths for Cube Pervious Concrete Samples ................................ .............. 111 4.11 Fracture Occurring Through the Aggregate ................................ ............................ 111

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xx 4.12 Second Proposed Site for the Pervious Concrete System Placement ...................... 114 4.13 (a) A Perforated Pipe Placed in Barrel (b) Image of B arrel ................................ ..... 118 4.14 Base and Sub Base Layers a) Coarse Aggregate Layer b) Fine Aggregate Layer .. 118 4.15 Cloth Fiber used between Coarse and Fine Aggregate Layers ................................ 118 4.16 Profile of the Pervious Concrete System Placed in the Barrel ................................ 119 4.17 Evaluation of Pe rvious Concrete Consistency ................................ ......................... 121 4.18 Rodding the Layers of Pervious Concrete in the Cube Mold ................................ .. 122 4.19 Compacting the Pervious Concrete in the Cube Molds Using (a) Direction 1 and (b) Direction 2 ................................ ................................ ................................ ............... 122 4.20 Covering the Pervious Concrete with a W et Jute Bag ................................ ............. 123 4.21 Removal of Pervious Concrete from Cube Molds (a) Close Up View (b) All Six Cubes ................................ ................................ ................................ ........................ 123 4.22 Placing Pervious Concrete Cubes in a Water Bath ................................ ................. 124 4.23 Placement of the Pervious Concrete Samples in Water Filled Container to Determine Percentage Voids from Volume of Displaced Water ................................ ............... 124 4.24 Compressive Strength Test and Fracture Path ................................ ......................... 128 4.25 Visual Observations (a) The Sample after Completion o f Compressive Strength Test (b) Breaking the Sample Further by Hand ................................ .............................. 128 4.26 Before and after Percolation (a) Bore Water Samples (b) Stream Water Samples 130 4.27 Samples Collected for Pathogen and B.O.D. Tests (a) Bore Well Water Samples (b) Stream Water Samples ................................ ................................ ............................. 130 4.28 Steel Roller for Compaction (a) Side View (b) Front View ................................ .... 136 4.29 Sieve Analysis (a) Phase II Coarse Aggregate, (b) Rajkot Coarse Aggregate, (c) Phase II Fine Aggregate, (d) Rajkot Fine Aggregate ................................ ............... 140 4.30 C oarse Aggregate (a) Rajkot (b) Phase II ................................ ................................ 141 4.31 Compressive Strength Fractures for M3 (a) Cubes and (b) Cylinders ..................... 144

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xxi 4.32 Compressive Strength Fractures for M4 (a) Cubes and (b) Cylinders ..................... 144 4.33 Fracture Through Aggregate ................................ ................................ .................... 145 4.34 Average Compressive Strength of Cylinders and Cube Mixes for Pervious Concrete Designed for 2000 psi (13.8 MPa) Strength ................................ ............................ 146 4.35 Relationship between Cylinder and Cube Average Compressive Strengths ........... 147 4.36 Average Compressive Strength with Sta ndard Deviations for All Batches ............ 148 4.37 Average Compressive Strength with Standard Deviations between Cylinders and Cubes at 7 day and Final Day Testing for all Batches ................................ ............ 149 4.38 Summary of Percent Porosity for All Batches ................................ ......................... 151 4.39 Summary of Hydraulic Conductivity for all Batches ................................ .............. 152 4.40 Summary of Hydraulic Conductivity for all Batches Using Falling Head Criteria 152 5.1 (a) Vanakbori Fly Ash, (b) Gandhinagar Fly Ash ................................ ..................... 165 5.2 Batches (a) Vanakbori and (b) Gandhinagar ................................ ............................. 167 5.3 Cubes (a) Van akbori and (b) Gandhinagar ................................ ................................ 167 5.4 Average Compressive Strength Result for Rajkot HVFA Concrete Samples ........... 168 5.5 U.S. and India HVFA Concrete Average Compressive Strength Results ................. 170 5.6 Summary of Average Compressive Strength Results and Standard Deviat ions between the U.S. and Indian Sources of Fly Ash ................................ ...................... 171 5.7 Aggregate (a) Storing and Cooling in a Shed and (b) Stockpiling ............................ 173 5.8 Temperatures of Stock Piled and Stored/Cooled Aggregate ................................ ..... 175 5.9 Campbell Scientific Datalogger (CR 10X) Used to Record Concrete Temperatures ................................ ................................ ................................ .............. 177 5.10 Installing the Thermocouple Into Concrete Sample ................................ ................ 177 5.11 Internal Curing Temperatures of Ambient Cured Fly A sh and OPC Samples During Trial 1 Testing ................................ ................................ ............................. 178 5.12 Internal Curing Temperatures of Heat Cured HVFA and OPC Samples During

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xxii Trial 2 Testing ................................ ................................ ................................ .......... 179 5.13 Surface of Samples after Heat Curing (a) Fly Ash Mixture (b) OPC Mixture ........ 1 79 5.14 View of (a) Water Curing Tank (i.e. Ideally Cured) and (b) Hot Weat her Curing Tank ................................ ................................ ................................ ............. 1 82 5.15 Hot Weather Simulation Tank (a) Boards to Keep Heat in (b) Close Up of Aluminum Foil Bubble Insulation ................................ ................................ ........... 1 83 5.16 Schematic of Hot Weather Simulation Tanks ................................ .......................... 183 5.17 Campbell Scientific (a) Datalogger (CR 5000) and (b) Setup for the Ideal and Hot Weather Simulation Tanks for Recording Concrete Temperatures .................. 184 5.18 Early Age Compressive Strength (a) No Heated Aggregate (b) Heated Aggregate ................................ ................................ ................................ ................. 188 5.19 Later Age Compressive Strength (a) No Heated Aggregate (b) Heated Aggregate ................................ ................................ ................................ ................. 189 5.20 Compressive Strength Results (a) No Heated Aggregate, (b) Heated Aggregate ................................ ................................ ................................ ................. 190 5.21 Modulus of Elasticity (a) No Heated Aggregate Concrete (b) Hea ted Aggregate Concrete ................................ ................................ ................................ 192 5.22 Permeability Testing Setup ................................ ................................ ...................... 193 5.23 Average Rapid Chloride Ion Permeability Test Results (a) No Heated Aggregate, (b) Heated Aggregate ................................ ................................ ............ 197 5.24 Length Change Apparatus ................................ ................................ ........................ 198 5.25 Length Change for No He ated Aggregate Samples ................................ ................. 200 5.26 Length Change for Heated Aggregate Samples ................................ ....................... 201 5.27 Effects of the Interaction of T and B on Compressive Strength .............................. 209 5.28 Effects of the Interaction of T and B on Permeability ................................ ............. 210 5.29 Effects of the Interaction of T and B on Percent Length Change ............................ 211 6.1 Sample Schedule for Competing Phase I II Testing ................................ .................. 228

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xxiii 6.2 Example of Finite Element Mesh and a Close Up of a Single Element Based on Dimensions of the Length Change Beam Made in Lab ................................ ............. 231 6.3 Difference between Elastic Potential Energy of Water Cured and Heat Cured OPC Concrete Sample after 90 Days of Curing ................................ ................................ 232 6.4 Schematic of Placement of the Thermocouple in Concrete Cylinder ....................... 234

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1 1. Introduction 1.1 Concrete and Urban Infrastructure having effective and well functioning infrastructure for urban areas grows. Many governments identify the modernization of urban infrastructure as a crucial step for future econo mic growth and competitiveness. However, executing plans for infrastructure in any nation is a challenge because it usually involves long term strategies and allocating large amounts of funding even during times of fiscal strain. During the next forty ye ars infrastructure is expected to cost approximately $70 trillion worldwide with most spending priorities occurring in the sectors of power/energy, residential, roads/bridges, rail, mining, healthcare, and water infrastructure (KPMG International, 2012; Se imens, GlobeScan, MRC McLean Hazel, 2007). 1.1.1 Concrete U se Much of the urban built environment is constructed from the material known as concrete. Concrete is one of the most versatile construction materials next to steel. Concrete infrastructure has had a historic presence dating back to the rule of the Roman Empire and possibly originating 2000 years before the Romans during Egyptian times. Even today the basic ingredients within concrete are rock (coarse aggregate), sand (fine aggregate), wate r, and a cement powder (once the powder is mixed with water it acts as a binder for the rest of the ingredients). A typical concrete mix (portland cement concrete) usually consists of 15% cement by weight (FHWA, 2012). Cement production for the world bet ween 2009 and 2010 was approximately 3310 million tonnes (USGS, 2012). Assuming the cement production is the potential consumption for the world and all

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2 cement is used for concrete products consisting 15% cement (by weight) then concrete consumption in 20 09 2010 was about 22.1 billion tonnes. This estimate exceeds the forecasted concrete consumption that was presented by Mehta and Monteiro (2006) (See Figure 1.1). Mehta and Monteiro presented Figure 1.1 based on consumption rates leading up to the year 2 002. Concrete consumption was estimated to peak at 16 billion tonnes (18 billion tons) or 2 tonnes/person when the population was about 10.4 billion people. With approximately 6.8 billion people between 2009 and 2010 per capita concrete consumption was a bout 3.3 tonnes of concrete/person. Note: At this time it seems as though no one entity keeps record of world consumption and production of concrete. Some countries or regions keep record of ready mix concrete use but in developing countries where concre te mixing occurs on site this does not seem to be taken into account. Figure 1.1 Concrete Consumption F orecast C ompared A gainst P opulation G rowth ( Mehta and Monteiro, 2006)

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3 1.1.2 Concrete Infrastructure Is a Source of GHG Emissions Concrete infrastructure comes with an environmental price. Cement production, alone, can contribute between 5 to 7% of global green house gas emissions (Mehta and Monteiro, 2006; Crow, 2008). Concrete has a large carbon footprint not just due to cement, but because it is used in large amounts in urban areas as a construction material. As cities continue to grow, demand for new and maintained infrastructure intensifies, which leads to a continued release of greenhouse gas emissions. Greenhouse gas emissi ons have been tied to global warming or where the average weather is subject to warmer changes (one definition of climate change) through scientifically based assumptions. 1.2 Climate Change in Urban Areas Scientific evidence points to urban areas as a m ajor contributor to greenhouse gas (GHG) forced climate change. Anthropogenic (relating to influence of human activity) waste heat in the form of heating and cooling buildings, traffic, construction, and industry coincides with increasing urban heat islan ds and doubled carbon dioxide emissions. Climate model projections isolating the response of urban micro climates to local (anthropogenic waste heat) and global effects, show that cities will experience an increase in maximum temperatures and frequency of hot nights. For cities such as Delhi or Los Angeles, 32 to 41 additional hot nights are a result of a low surface heat capacity, low soil moisture, high energy gains throughout the day, and rapid release of heat from the soil ( McCarthy, Best & Betts, 20 10 ). However, a particular challenge in addressing climate change and (GHG) emissions is engaging cities to have a personal connection with climate change. Various

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4 cities across the world do not see climate change as being an issue, because there are uncertainties or skepticism regarding the cause and seriousness of climate change; climate change is believed to be too distant of a problem, or making changes are costly and undesirable for the current lifestyle, and climate change is not a priority compa red to other issues requiring government action (Lorezoni, Cole, Whitmarsh, 2007). Globally, city governments are constantly balancing maintenance, design, and financial obligations to keep urban infrastructure reliable and safe. However, climate change can exacerbate these common infrastructure issues. In fact, growing research in sustainable infrastructure and climate action planning has provided evidence that failing to address the results of climate change and greenhouse gas emissions could lead to r isks of increased water demand, heat island effect, declining air and water quality, new and old health risks emerging, and increased stresses and deterioration on the operation of urban and rural infrastructure (The World Bank, 2008; McCarthy, Best, & Bet ts, 2010, Mehrotra, Natenzon, Omojola, Folorusho, Gilbride, & Rosenzweig, 2009). R ecently, urban areas are experiencing the effects of a changing climate. Some examples of present risks for infrastructure, in both developed and developing countries, base d on current climatic conditions are described in the next few paragraphs. Note: The next few examples of climate change and current risks make reference to India and the United States because this dissertation has a focus on India. 1.2.1 Flooding or Drought in Urban Areas Every year Indian cities experience flooding from seasonal monsoons that result in damage to urban infrastructure and increased health risks, however, urban infrastructure may have a contribution to flooding if inadequate stormwa ter control

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5 mechanisms are not developed or improperly developed. But for cities in arid to semi arid regions any type of water is an important commodity to conserve. As will be explained in a later section this dissertation uses Rajkot, India as a cas e study for discussing urban concrete infrastructure opportunities to address carbon mitigation and climate adaptation. In a city like Rajkot, India the climate is hot and dry but flooding can occur with just rainfall intensities of 100 mm (4 in) due to n onexistent or few storm water management strategies and hard basaltic rock underlying the top soil of the terrain. But a concern other than flooding is the potential for climate change to produce more heat and lower rainfall. For the year 2012, in the st ate of Gujarat, India 14 districts and 152 talukas (subdivision of a district) declared a state of drought due to receiving less than the average rainfall of 33 to 152 cms. Water sustains life in many of desert like regions but urban stormwater management solutions in countries such as India do not currently take into account the climate change risks for different regions. 1.2.2 Extreme Temperatures in Urban Areas As mentioned previously extreme temperatures can become another concern for urban infras tructure. Road infrastructure is a priority for most countries. Currently more than 70% of paved roads in India are bitumen, with some major highways being concrete. However, there is increasing interest in investing in road projects using concrete. Th e bitumen (CMA, 2010c). Bitumen for asphalt pavements has to be imported into India (CI I, NRC, Ambuja Cement, 2004). The performance of concrete pavements has been successful in countries like the U.S. however in 2011 the world experienced one of the

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6 warmest years on record leaving a reminder that climate change can affect the soundest of i nfrastructure. Sections of concrete pavement buckled due to trying to expand in weather that was consecutively above 32.2 o C (90 o F). The Minnesota Department of Transportation explained to Minnesota Public Radio News that concrete pavements had little roo m to expand near congested joints thus causing a lift to occur. In Oklahoma City a prolonged heat wave (+37.8 o C [100 o F ]) caused concrete roads to buckle near joints similar to Minnesota, and the incidents were recorded across the entire state of Oklahoma. Research on climate change and concrete infrastructure has also shown that concrete infrastructure will face additional deterioration, carbonation, and chloride induced corrosion as a result of climate change events and increased greenhouse gas emissions ( Wang, Nguyen, Stewart, Syme, & Leitch, 2010 ). Concrete has been identified as having a contribution to greenhouse gas emissions and also having susceptibility to damage and deterioration from the effects of changes in the climate. But the unique prope rty of concrete, as stated previously, can be its versatility and ability to serve various purposes (such as climate adaptation) by adjusting the mixture design to include other materials aside from the four key ingredients. Additionally, if these materia ls can replace the use of cement then green house gas emissions can be reduced. 1.3 Concrete Infrastructure for GHG Mitigation and Climate Adaptation If cities can identify an association with climate change then an important next step can be the asses sment of effective and efficient adaptation or mitigation strategies and policies for urban areas and its infrastructure. Urban areas are complex systems and the vulnerability of each city depends on geographic, sectoral, and social attributes

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7 (Mehrotra e t al., 2009). Many organizations such as the World Bank, Intergovernmental Panel on Climate Change (IPCC), Environmental Protection Agency (EPA), and International Council for Local Environmental Initiatives (ICLEI) are providing local governments with re sources and ideas that can help urban areas prepare, prevent, or adapt to the possible effects of climate change. The study in this dissertation commenced with Integrative Graduate Education a nd Research Traineeship program on Sustainable Urban Infrastructure and ICLEI South Asia to develop sustainability assessments of infrastructure and develop decision support tools customized to Indian infrastructure (i.e. greenhouse gas (GHG) inventories that includes the building, transportation, construction material sectors) for cities in South Asia. Although cities may not know the exact vulnerabilities that urban areas and con crete infrastructure face under climate change and GHG emission increases it is expected that increasing GHG emissions leads to an increased risk of climate change occurring, and with climate change there is the likelihood that flooding, drought, and incre asing temperatures (along with heat islands in urban areas) will have an influence on urban areas and infrastructure. This dissertation proposes that two concrete technologies exist to aid in climate adaptation and carbon mitigation for urban areas; pervi ous concrete and high volume fly ash concrete. 1.3.1 Pervious Concrete Past and Contemporary Research Pervious concrete is known as a permeable, gap graded, or porous concrete which allows water to percolate through intended voids in the concrete. A mixture design usually consists of higher proportions of coarse aggregate compared to conventional

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8 concrete, a thin layer of cementitious paste to bond and cover the aggregate, and little to o form of the pervious concrete) as a construction material for buildings (Ghafoori & Dutta, 1995). However, today pervious concrete is better known in the U.S. as a best management practice (BMP) technology because it can serve as a st ormwater management tool that can recharge the groundwater, reduce stormwater runoff, reduce the level of contamination in run off, and help lower the heat island effect due to its open pore structure and its lighter color than asphalt pavements (Tennis et al, 2004) Also, these same properties have led it to its description as a sustainable concrete. Research conducted at the University of Colorado Denver (UCD) revealed these various benefits in a pervious concrete pavement field installation (Hager, 20 09). The successful installation involved the incorporation of 20% fly ash to offset the use of cement, 10% replacement of sand with crushed glass in the sub base layer and the test section was monitored for deterioration, clogging, stormwater quality and reduction of the heat island effect. The results led to recommendations on design, placement and curing in order to produce durable pervious concrete pavements with sustainable aspects for urban areas in research exposing the benefits and promoting the use of pervious concrete. Between 2006 and 2009 research topics ranged from lab and field tests on pervious concrete to analyzing the capabilities of pervious concrete to filter compost effluent resulting from agriculture. The various types of research regarding pervious concrete can be found in appendix A Tables A.1(a) through A.1(e) which lists the research titles, authors, and objectives. Many of these studies have

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9 encouraged that cities use pervious c oncrete for other applications besides pavements and are listed below: Alleys and driveways Highway shoulders Sidewalks Low water crossings Sub base for conventional concrete pavements Patios Walls Noise barriers 1.3.2 High Volume Fly Ash Concrete Research with a Focus on Thermal Properties High volume fly ash (HVFA) concrete has been identified as incorporating more than 50% of fly ash by mass of total cementitious material into conc rete (Malhotra & Mehta, 2008). In the 1980s Malhotra began testing HVFA concrete by using Class F and Class C fly ash. Using higher volumes of fly ash in concrete proved to give concrete improved mechanical properties and possess benefits such as those listed in Table 1.1 (Giaccio & Malhotra, 1988; Malhotr a & Mehta, 2008, American Coal Ash Association [ACAA], 2003; ACAA, 2002). The benefits of fly ash concrete have been taken beyond the physical, chemical and economic characteristics such that the use of fly ash is an indirect solution to green house gas ( GHG) emissions and is a means for reducing energy use from cement manufacturing. In addition, the use of fly ash is associated with avoiding landfill, and reducing the overconsumption of virgin materials.

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10 Table 1 .1 Summary of the B enefits of Fly Ash C oncrete Benefits of fly ash concrete High performance/high ultimate strengths Can compensate for fines not found in some sands Improved workability and flowabilit y Lowers water demand Reduced bleeding and segregation Reduced concrete shrinkage Reduced heat of hydration Reduces wear on delivery and plant equipment Improved durability through reduced permeability Increased resistance to sulfate attack, alkali silica reactivity (ASR), and other forms of deterioration In one particular study performed at the University of Colorado Denver replacement of cement with 20% and 40% fly ash in concrete mixes reduced greenhouse gas emissions by 21% to 36%. The study was also unique in showing how per capita usage of cement, within the City and County of Denver bound total Denver to understand how the environmental impact of the conventional and fly ash concrete mixes could be quanti fied and compared with a combined life cycle assessment and material flow analysis. Also such information could be used as a tool for making decisions about the impacts we want future infrastructure to have. One particular characteristic noted from a l iterature review on HVFA concrete was the reason for incorporating it into concrete in the 1930s; fly ash was and has been used to reduce the heat of hydration in mass concrete (Malhotra and Mehta, 2008). In a study by Malhotra along with Rivest and Bisai llon (as cited by Malhotra & Mehta, 2008) several concrete monoliths (some made from HVFA and the others made from 100% cement) showed a difference in temperature of about 22 o C (39.6 o F) with the lowest

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11 temperatures occurring in the HVFA concrete monoliths. Cements available today have such a high reactivity that a high heat of hydration is likely to occur even in structures with thicknesses less than 50 cm (~20 in). Although the properties of modern cement r a structure susceptible to thermal (excessive temperature differences between the concrete and the surrounding temperature) and drying shrinkage (contracting of hardened concrete due to loss of capillary water) cracking. These two types of cracking are especially a problem during hot weather concreting. Table A.2, found in Appendix A summarizes just a handful of past research on fly ash concrete related to hot weather concreting applications or experimentations. Hot weather concreting means that precautions must be taken when concrete mixing and placing is occurring at temperatures above 32 o C (90 o F) or when concrete temperatures are somewhere between 25 o C and 35 o C (77 o F and 95 o F). Common solutions for hot weather concreting are the following (PCA 2002). Cool concrete materials before mixing Schedule concrete placements to limit exposure, thus avoiding pouring during the hottest part of the day Use chilled water or ice as part of the mixing water Use of a Type II moderate heat cement While curing use sunshades, misting, or fogging to limit moisture loss Apply moisture retaining films after screeding Studies on HVFA concrete have shown that thermal and drying shrinkage cracking are minimized in the concrete as a result of the properties of the fly ash (Malhotra & Mehta,

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12 2008; Ravina, 1981; Mehta, 2002; and Senthil and Santhakumar, 2005). HVFA concrete lowers internal curing temperatures due to fly ash having a lower reaction compared to cement. Ravina studied lower percentages of fly ash in concre te, but both Ravina and Mehta express that hot weather concreting with fly ash decreases water demand during mixing. Also, high concrete temperatures have been shown to reduce strengths in concrete, however, both studies by Mehta (2002) and Ravina (1981) proved that fly ash concrete strengths were typically higher than a reference mixture made with ordinary portland cement at later ages when both types of concretes were cured in hot temperatures. Other research has shown that the long term performance of fly ash concrete have led to more durable structures that require less maintenance (ACAA, 2002). Mehta (2002), Senthil and Santhakumar (2005) monitored the internal curing temperature of fly ash concrete and showed that fly ash can prevent thermal cra cking The study by Senthil and Santhakumar (2005) is one of the few studies where the mixture designs involved the use of blended cements from India. In India blended cements can consist of fly ash and cement or ground blast furnace slag and cement whic h are blended during the cement manufacturing process. The percentage of fly ash in the blended cement study by Senthil and Santhakumar was not specified, however the results revealed that the heat of hydration could be about 5 o C (9 o F) higher for the blen ded cements when compared to a general purpose cement and a high strength cement. The surprisingly high heat of hydration may have been attributed to the fineness of the grinding, according to the authors; nevertheless the strengths were comparable to the high strength cement mixture. Mehta emphasized that high volume fly ash concrete (with Class F fly

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13 ash) would be most beneficial in keeping temperature increases under 30 o C (54 o F) and under such temperature maintenance thermal cracking was preven ted for a foundation placed under warm and humid conditions When 50% or more fly ash is utilized, the fly ash and the cement complement one another, such that some heat is generated from the presence of cement but part of the heat is concentrated on the acceleration of the pozzolanic reaction. Besides possess ing beneficial properties for hot weather concreting HVFA concrete has other thermal properties that could be related to energy efficiency. The research by Bentz et al. (2010) was unique in the aspect of examining the thermal benefits of hardened fly ash concrete while the previous authors monitored temperatures of fresh concrete and then evaluated the mechanical properties after hardening. Although the mechanical properties were of importance to Bentz et al. the goal of the research was to evaluate the e nergy efficiency or insulative potential of high volume fly ash concrete for use in buildings (residential or commercial). Bentz, et al. did comment that the aggregates affected the thermal conductivity of the HVFA concrete; however, other research refere nced in Table A.2 did not make reference to aggregate effects. Thus, it may be beneficial to research the temperature of freshly mixed fly ash concrete as affected by temperature of aggregate. 1.3.3 Main Goal and Knowledge Gaps The research regarding c limate change and carbon dioxide should not be overlooked. The literature review and recent events have supported the idea that carbon is linked to climate change and urban areas are facing a new challenge that could bring flooding, drought, and rising a nd prolonged temperatures. There is no doubt that the

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14 climate change and carbon dioxide expose society to environmental and health risks. But, there is minimal research regarding the effects of carbon dioxide and climate change on the urban infrastructur e that society depends on. Without proper infrastructure planning and designing, that takes into account climate change impacts, there is the possibility that new infrastructure could experience premature deterioration while the deterioration rate of ol der infrastructure could be exacerbated. Based on the literature review very few studies exist that explore how concrete infrastructure will be affected. However, the literature review did highlight the benefits that pervious concrete and high volume fly ash concrete could contribute towards climate adaptation. Despite the 80 plus years of research regarding both pervious concrete and high volume fly ash concrete many city governments are unaware of these benefits and therefore do not encourage the regul ar use of these two concrete technologies (Ghafoori and Dutta, 1995; Solis, Durham, Rens and Ramaswami, 2010). Studies by Hager (2009) and Reiner (2007) are great examples of how they used their research to demonstrate and improve on the advantages of p ervious concrete and fly ash concrete. Recall, that the study by Reiner also indicated that fly ash use in concrete designs can reduce emissions resulting from cement and the manufacturing of concrete. In another study by Reiner along with Ramaswami, Hill man, Janson, and Thomas ( 2008 ), it was found that just by including the embodied energy of key urban materials such as concrete, quantification of per capita GHG emissions was improved for the city of Denver and became the benchmark from which the city cou ld begin developing ways in reducing their emissions as whole or within certain sectors such as the design of construction materials.

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15 Main Goal of Thesis: carbon mitigation and climate adaptation in cities. Summary of Knowledge Gaps However, in order to support these recommendations the following knowledge gaps, which we re identified from the literature review, are studied further and play a major role in this dissertation. GHG emissions ready mix concrete operations in a city (2007). However, for cities t hat rely on on stie mixing operations, such as in developing countries (i.e. India), are emissions comparable to those of where cities primarily use ready mix companies? Pervious Concrete There has been no research regarding the ability to transfer well established and research supported pervious concrete designs to other regions having material differences. Research has indicated that size and shape of aggregate can change certain properties of the pervious concrete but it is unclear, if all materials differed (aggregate, water, cement), whether these changes drastically affect strength, porosity, filtration, and hydraulic conductivity all at once. High Volume Fly Ash Concrete It is already known that HVFA concrete is a well established solution to lowering the heat of hydration and preventer of thermal and drying shrinkage cracks during hot weather concreting. However, the literature on climate change has indicated that there is the likelihood of

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16 extended periods where temperatures will rise abo ve average temperatures. The question that research has not quite answered is how does do these prolonged high temperature events affect materials before mixing? How are fresh concrete properties affected after mixing when materials have been affected by the hot weather? Do current hot weather curing methods work for extended periods of high temperatures? Will hardened properties change dramatically when temperatures extend past 28 or more days of curing? The main question that has been left unanswered is whether fly ash has the capabilities of mitigating the effects of extended periods of heat even when required to cure for 56 to 90 days? 1.4 Thesis Objectives The collaborative work with ICLEI South Asia and University of Colorado Denver presented t he opportunity to study the knowledge gaps mentioned in the previous section. Thus the main objectives of this research were the following This study applied the powerful tool of MFA LCA to determine the environmental impacts of pervious and HVFA concrete compared to ordinary portland cement ( OPC ) concrete in a developing country In this study a c omparative assessment of pervious concrete mixture designs for s tructural and environmental benefits across the U.S. and India was performed In this study it was necessary to d etermine whether there are structural and durability benefits from HVFA in concrete mixtures when subjected to extreme hot weather conditions

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17 1.5 Organization of Thesis 1) In Chapter 2 the case study is introduced. The city of Rajkot, India is described through climate, cement consumption, stormwater management, and current construction GHG mitigation is also discussed discussed in Chapter 3. The manufacturing process as well as carbon mitigation strategies being implemented by the industry in India is emphasized. The chapter ends with a material flow and life cycle analysis of concrete for Rajkot, India but generally applicable t o any city in the state of Gujarat. 3) In Chapter 4 the methods and results of a small demonstration of a pervious concrete system that occurred in Rajkot, India is disclosed as Phase I of the pervious concrete project. This part of the study led to a c oncern over comparisons in strengths between cube and cylinder samples. As such Phase II is used to discuss the attempt at establishing a relationship between cubes and cylinder properties. 4) In Chapter 5 Phase I of the HVFA fly ash study involves a co mparison between typical fly ash properties in India and the U.S. and is used to discuss the importance of design and test of high volume fly ash concrete mixtures. Cubes and cylinders strength results are compared for the U.S. and India as part of Phase II. Phase III is used to identify the benefits of high volume fly ash concrete over ordinary Portland cement concrete when subjected to representative temperatures of hot days experienced throughout arid and semi arid regions of India. The chapter descri bes a multiple linear regression analysis used to determine the effects of a variety of experimental conditions and compositions on

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18 ordinary Portland cement concrete mixtures versus high volume fly ash concrete mixtures. 6) The study ends with Chapter 6. A summary of the major findings are discussed as well as recommendations on how to improve on the study

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19 2. Case Study Location: The City o f Rajkot India 2 .1 Demographics, Population and Climate Rajkot is located in the state of Gujarat in Western India (Refer to Figure 2.1) The climate of Rajkot is hot and dry throughout much of the year thus representing a semi arid region. Mild temperatures can be about 20 o C (68 o F) but during the summer, during the months of March through June, temperatures range between 24 o C to 42 o C (75.2 o F to 107.6 o F). Rajkot can exp erience acute droughts at times but, during the monsoon period (June to September) the city can receive an average of 500 mm (19.7 in.) of rain Figure 2.1 Location of Rajkot within the state of Gujarat, India ( Google Maps)

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20 The population of Rajkot according to a 2001 census was approximately 1,002,000 and has increased to about 1.4 million. A growth rate of 79.12% was established in the 2001 census for the years (1991 to 2001) but was partly attributed to extending the city limits to include other villages. Rajkot city is connected to other parts of the country by air, two railway stations, and major roads that link Rajkot to several cities within the state including to the sta te capital Ghandinagar. Rajkot is considered an industrial town and the economy is based on over 400 foundries, engine oil manufacturing, machine tools, engineering and auto works, castor oil processing, jewelry, handicrafts, clothing, medicines, and agri culture (Rajkot Municipal Corporation, 2006). economic, industrial, and educational center has led to continued urbanization and the need for a comprehensive development p lan. Rajkot Municipal Corporation city development plan for the years 2005 2012 was developed under the Jawahar Nehru National Urban Renewal Mission (JnNURM) such that the goal of the city was identified as being responsive, economical, efficient, producti ve, and equitable. While under the mission of the JnNURM, Rajkot has also committed to incorporating clean development strategies so that infrastructure investments would lead to an improved urban Governments for Sustainability), South Asia Urban Climate Project has been working with Rajkot to begin implementing sustainable infrastructure interventions that address the infrastructure problems identified in the city development pla n.

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21 2.2 Rajkot Construction and Concrete Infrastructure industry. The highest employment (28% of total population) occurs within the sector of manufacturing. Rajkot does not hav e a cement manufacturing plant within city limits. The closest plant is located about 116 km (72 mi) outside of the city in the area known as cement manufacturing plants are located within the state of Gujarat and the farthes t plant about s 295 km (183 mi) from Rajkot. Cement in Rajkot is used for various construction materials such as reinforced cement concrete, prestressed concrete, paver blocks, cement blocks, and asbesto s piping. Figure 2.2a and 2.2b shows an example of paver blocks made in Rajkot. (a) (b) Figure 2.2 Paver B locks (a) R emoval from M olds (b) D esign on S urface of B locks Major cement companies that deliver cement throughout the state of Gujarat are Hathi Cement (part of SaurashtraCement Limited), Gujarat Sidhee Cement Limited, UltraTech Cement Limited (part of the Aditya Birla Group), Ambuja Cements Ltd., Shree Digvijya Cement Co. Ltd., HMP Cements Ltd, Sanghi Industry Ltd., JK Lakshmi Cement Ltd., a nd Jaypee Cement (CMA, 2010c). There is one ready mix concrete plant within the city limits which is owned and operated by the cement manufacturing company known as

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22 Lafarge. Ready mix concrete, in Rajkot, is only used in large construction projects. Lar ge construction projects are associated with bridges, fly overs, railway, skyscrapers, and bus rapid transit system (BRTS) roads (M. Joshi and Mr. Girish [contractor] personal communication, March 8, 2011). The majority of the construction seen in Rajkot used the method of on site mixing. 2.2.1 Personal A ccount of C onstruction Collaborative work with Rajkot Municipal Corporation allowed for personal observations and communications to be made with a city assistant engineer and city civil engineer as well as a structural engineer/owner of Lakhlani Associates. Additionally the collaborative work allowed for the majority of the field research, presented in this dissertation, to be performed on site where a water/tower (designed by Lakhlani Associates) w as being constructed. The construction process of the water tower revealed the following about most of the city concrete construction projects: Ready mix is expensive compared to on site mixed concrete and is not considered necessary for all city projects Cement bags and aggregate are delivered in bulk to the site ( Refer to Figure 2.3 for example of stock piled materials) Most common cement used on site was Hathi, Ambuja, UltraTech, and Sidhee cements At this particular site water used for concrete mixture design was taken from a bore well drilled on site

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23 Each batch required that aggregate be weighed using a large scale located on site that was calibrated daily. (Refer to Figure 2.4) Concrete was mixed with portable diesel powered commercial concrete mi xers (See Figure 2.5) Mixed concrete was transported by wheelbarrows or up several heights by a bucket and pulley (See Figure 2.6 and Figure 2.7). Bamboo was used for scaffolding and concrete forms Both men and women worked and lived on site Most of the laborers were from villages nearby Not all laborers had safety equipment to wear. The laborers who worked with the placing of steel reinforcement are considered skilled workers and get paid more than those working with just concrete Figure 2. 3 M aterials S tock Piled D irectly on C onstruction S ite

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24 Figure 2. 4 Large S cale U sed for Measuring Aggregate and Cement b efore Batching Figure 2. 5 M aterials T ransferred from S cale i nto P ortable D iesel Powered M ixer Figure 2. 6 Laborers P lacing C oncrete

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25 Figure 2. 7 Cement B eing E mptied from the Bucket and P ulley M achinery 2.2.2 Rajkot Concrete Infrastructure In 2001 the city of Rajkot occupied an estimated 10,485 hectares (25906 acres) of land. Figure 2.8 displays the breakup of land use in Rajkot. Abou t 74% of the city limits were developed, with residential areas occupying a little more than half of the developed (i.e. residential, commercial, industrial, transportation, public, recreational, and other) area. Commercial use is mostly reserved for reta il marketing, industrial use includes 369 units of various industries within the city limits and public use include hospitals, schools, and government office buildings. Investment on infrastructure projects in Rajkot occurs in the sectors of traffic and transport, water supply, drainage, stormwater drainage, housing and the urban poor, public works, and solid waste management. The majority of built infrastructure is constructed of concrete. The typical concrete infrastructure seen in Rajkot can be descr ibed as follows and are depicted in Figures 2.9 through 2.14: Recreational/Office/Home/ Apartment Buildings Roads Sidewalks

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26 Wastewater Treatment Plants Check dams Water piping systems Bridges Water Towers 1 Hectare = 2.471 Acres Figure 2. 8 Breakup of L anduse within City L imits of Rajkot (Rajkot Municipal Corporation, 2006) Figure 2. 9 Small R esidential B uildings N ear the E dge of C ity L imits

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27 Figure 2.1 0 Indoor S t a dium Figure 2.1 1 Buildings Near the Center of the C ity Figure 2. 12 Waste W ater T reatment P lant

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28 Figure 2. 1 3 Construction of H ousing Figure 2. 14 Construction of a W ater T ower Concrete plays a major role for the infrastructure found in Rajkot. Despite on site mixing seemingly lagging in terms of modern construction, Indian structural engineers have been successful in demonstrating the advantages of concrete design for structure s. The indoor stadium structural system designed for the stadium. One unique aspect that made t he design innovative was a reinforced concrete tripod system which has the purpose of transmitting roof forces to the ground. The stadium is just one example of how Rajkot has a distinctive type of city management that is eager to collaborate with private and government entities to try new ideas that allow the city to advance in terms of

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29 technology, business, industry, and infrastructure. In fact the city development plan for 2005 GHG emissions and energy consumption and achieve a productive, efficient, equitable, and Urban Renewal Mission (JnNURM). 2.3 Future GHG Mitigation and Climate Adaptation Goals Rajkot has already demonstrated how the goals of the city development plan are being achieved. On the roofs of many buildings in Rajkot, evacuated tube solar water heaters have been installed (See Figure 2.15). This type of device has been used fo r some years and is currently cheaper than gas water heaters; consequently it avoids CO 2 that could result from gas powered water heaters. At the Rajkot Municipal Corporation western zone office a solar photovoltaic system was installed to partially power the office. Also, one of the Rajkot Municipal Corporation offices was designed with an open foyer so that the various floors were cooled through passive cooling. Figure 2.16 shows the open foyer which included a nice landscaping of plants. Other interv entions that were being implemented during 2011 was the construction of a Bus Rapid Transit System, solar powered lights for parks, investing in energy saving technologies for schools, and installing more city trash bins in communities throughout the city for waste collection. Some of the interventions were a result of the collaborative work with ICLEI South Asia. The collaboration was meant to showcase clean and efficient technologies for infrastructure and to find what could be successful for the city a s a long term method of use or design. Rajkot has been willing to implement new ideas into their infrastructure design even before collaborating with ICLEI South Asia. As stated in the city

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30 development plan some of the priorities of the city have been im provement of roads and stormwater management. The city has experimented with stormwater management methods and fly ash concrete roads. Figure 2.15 Tube S olar W ater Heaters M ounted on the R oofs in Rajkot Figure 2.16 Rajkot Municipal Corporation O ffice with P assive C ooling F oyer D esig n

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31 2.3.1 Stormwater/ R ainwater H arvesting Through a personal communication with Y. K. Goswami (March 9, 2011), Assistant Engineer at Rajkot Municipal Corporation, Rajkot has been involved in urban rainwater harvesting or stormwater management trials. For example within certain residential areas, parks or gardens have been built such the park acts like a recharging pit or detention pond when it rains. In Figure 2.17 an example of one of these parks can be seen before it is filled by stormwater. The purpose of these parks is to direct the stormwater into these pits so that the water either seeps i nto the ground or in some cases drains into a storage tank below constructed below the park. The depth excavated for these parks will vary based on the rain events expected for an area. In Figure 2.17 it appears as though the depth is at least 1.2 m (4 f t). Figure 2.18 shows the same park after storm water had drained into the park. The rain event filled the total depth of the park. Figure 2.17 Recharging P it or D etention P ond P ark B eing C leaned Depth Depth

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32 Figure 2.18 Park F illed with Stormwater A fter a Rain E vent 2.3.2 HVFA C oncrete R oad P roject project was completed in partnership with Ambuja Cement, Natural Resources of Canada, and the Co nfederation of Indian Industry. The project used a high volume fly ash concrete mixture design. The mixture design demonstrated that initial costs for concrete roads could be reduced through the use of local materials and waste products such as fly ash. The project presented an alternative to bituminous roads. The road extends 2.3 km (1.4 mi) through the campus of Saurashtra University in Rajkot. The material design included grade 53 ordinary portland cement (OPC) from Ambuja Cements Ltd. and fly ash f rom Sikka thermal power plant located in Sikka, Gujarat, which is about 115 km (71 mi) from the city of Rajkot. Two concrete layers made up the design of the road, such that the 150 mm (6 in) thick bottom layer was from a 50% high volume fly ash concrete mixture and the 50 mm (~ 2in) thick top layers was made from a 30% fly ash concrete mixture. The top and bottom layer reached a compressive strength of about 41.2 MPa (5976 psi) and 40.1 MPa (5816 psi) respectively. Design compressive strengths for concr ete roads in the U.S. generally are at least 28 MPa (4000 psi) and project was at least 12 MPa (~1800 psi) greater than the design

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33 compressive strength. Figures 2.19a and 2.19b show the surface of the concrete pavement 6 years after it had b een constructed. Although Figure 2.19a shows a two wheeler and tractor using the road, heavier traffic such as commercial vehicles can be expected on the road as well. Figure 2.19b shows the different wearing down of the surface of the concrete. The pro ject brought about other concrete pavement construction and in 2011 a high volume fly ash concrete road was being constructed around the Raiya waste water treatment plant in Rajkot (See Figures 2.20a and 2.20b). (a) (b) Figure 2.1 9 HVFA Concrete R oad on Saurashtra University Campus ( a) Two W heelers and T ractor on the Road (b) C lose up of the S urface of the R oad (a) (b) Figure 2. 20 Raiya WWTP Site (a) P lacing C oncrete (b) C uring C oncrete

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34 2.3.3 Collaboration b etween UC Denver, ICLEI South Asia and Rajkot Municipal Corporation decided that there was further interest in trying new stormwater management systems or best practices and the need to further study the comp ressive strength with high volume fly ash concrete. Originally all parties preferred an actual field installation of a pervious concrete system and anticipated the results for compressive strength, water percolation, and water quality improvements. The p arties agreed that the pervious concrete field demonstration would be constructed at the Raiya WWT site where the fly ash concrete road was being placed. As part of the fly ash concrete project there was significance placed on determining whether other lo cal fly ash sources (besides the Sikka power plant fly ash used in Saurashtra University road) would produce similar compressive strengths. There was an overall interest in promoting the use of these concrete technologies to facilitate reforms and improvem ent of urban infrastructure for cities interested in climate adaptation and carbon mitigation (carbon mitigation through quantification of reduced GHG emissions from use of the pervious concrete and fly ash concrete). The remainder of this dissertation wi ll discuss the collaboration between parties in detail. A material flow and life cycle analysis (MFA LCA) of cement and concrete will be discussed in Chapter 3. The MFA LCA was modeled after the study conducted by Reiner (2007) with the goal of determini ng the contribution that cement use had in cities such as Rajkot. Chapter 4 provides the discussion of the potential applications of pervious concrete in Rajkot for stormwater management while Chapter 5 discusses the potential for HVFA

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35 concrete to be used as a climate adaptation strategy in extreme hot weather conditions that could occur in a semi arid region like Rajkot.

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36 3. Carbon Mitigation Through Concrete: An MFA LCA Approach 3.1 Bottom line: Cement and Concrete M anufacturing in India and the US The objective of this study was to quantify CO 2 emissions resulting from Indian cement manufacturing and concrete production and compare results to the U.S. L iterature reported different cement emission factors ranging from 0.6 to 1.0 tonne of CO 2 /tonne of cement (0.6 to 1.0 lb CO 2 /lb cement) (e.g. WBCSD, 2010; Parikh, Sharma, Kumar, Vimal, IRADe, 2009) It was unclear which would be the most appropriate emissions factor. Thus initial findings resulted in the review of Grasim Industries sustainability report published for th e year 2007 2008. Grasim ACC Ltd. and Ambuja Cements Ltd. are major competitors in Indian cement manufacturing. Both Grasim and Ambuja are p rovider s also one of the only available reports that had created a CO 2 emissions and energy inventory that could be compared to the thorough inventory published for the U.S. cement industry by the Portland Cement Association (Marceau, Nisbet, VanGeem, 2010). ncluding subsidiary companies) account of total materials, energy, and electricity used in the year. In addition, CO 2 emissions for direct energy (thermal energy) and indirect energy (purchased electricity) were calculated all cement manufacturing plants had been converted into the dry precalcination process. There are three main processes for manufacturing cement and each are discussed later in this chapter. However, the dry precalcination process is currently the most e nergy efficient process available for cement manufacturing (about 1.3 GJ/tonne of clinker [559 Btu/lb clinker] more efficient than the

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37 wet process). The precalcination process makes use of the waste heat from the kiln and clinker cooler to preheat the ki ln material by use of cyclone preheaters installed before the kiln (up to 6 cyclones can be installed). Both in the U.S. and India the dry process is used to produce more than half the total cement produced, however the dry process in the U.S. only accounts for 53% of total production, but in I ndia it is 98% (Maceau et al., 2010 and CMA, 2010c). Table 3.1 compares the direct and indirect energy consumption for India (represented by Grasim) and the U.S. through the dry precalcination process. Table 3.1 C omparison of Energy Use per Tonne of Cem ent Between the U S Cement Industry and asim Industries Values are in GJ/Tonne of cementitious material 1 GJ/Tonne of cement = 429.92 Btu/lb of cement Source: Marceau, Nisbet, VanGeem, 2010; Grasim Industries Ltd, 2008 An overview of an LCA is given in the next section, but a key step in an LCA is choosing a functional unit. In order to relate inputs and outputs of the cement

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38 manufacturing process from two different countries the functional unit has to be the same. The functional unit for the LCA (cradle to gate) given in Table 3. 2 was a unit final emissions in terms of tonnes of CO 2 is used to rep resent the use of alternative materials that are used in replacement of a percentage of cement. These materials can be fly ash silica fume, or slag. In the U.S. the use of these materials is usually called blended cements (Type IP, Type IS, Type I( PM), and Type I(SM) where P = pozzolana, S = slag, M = modified) and in India these cements are called portland pozzolana cement (PPC) (when fly ash is used) and portland blast furnace slag cement (PBFS). Blended cement production in the U.S. is about 2 t o 3% of total production while in India it is about 60 to 70% (USGS, 2010; CMA 2010c). Use of these cementitious materials ideally reduces cement clinker demand for a unit mass of cement product as a result of less kiln fuel being burnt. Additionally, us e of cementitious materials avoids disposal or stock piling of fly ash and slag. However, emissions do arise from transportation of the fly ash and slag to the cement manufacturing site and additional emissions may occur from any grinding that is necessar y for slag. Since India produces large amounts of cementitious materials including it as the functional unit in a life cycle inventory as Grasim did is a benefit. However, it is not necessary because if there has already been a reduction in thermal and electrical energy due to less clinker is being processed this would be reflected in the inventory without using cementitious as the functional unit. In Table 3.1 direct energy for the U. S. and Grasim does not always come from the same fuels. According

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39 natural gas are not used as they are in the U.S. However, the coal consumption appears to be similar and there is about a 20% difference in the use of petroleum coke. Often use of alternative waste fuel materials (which are discussed in detail later in this chapter) in the kiln reduces carbon dioxide emissions. In this case, the U.S. cement industries on average use more waste materials as kiln fuels compared to Grasim. For indirect energy, t here is a large difference in electricity purchased between Grasim and the U.S. Grasim uses about 65% less purchased electricity compared to the United States. In India captive power plants generate electricity on site and reduce the need to purchase ele ctricity from state grids. Overall Grasim uses approximately 10% less energy in the manufacturing process compared to the average cement industries in the U.S. that use the precalcination process. Table 3.2 Summary of Energy Use and Emission Factors fro m Direct and Indirect CO 2 Emissions between India and the U S India has smaller emissions from electricity due to use of captive power on site **This number is net electricity purchased however, with the inclusion of indirect emissions this leads to about a 7% increase in emissions for the U.S. cement manufacturing. 1 GJ/Tonne of cement = 429.92 Btu/lb of cement, 1 kWh/Tonne of cement = 1.54 Btu/lb, 1 kg/tonne = 2 lb/short ton Table 3.2 uses the data from Table 3.1 to calculate electricity and cement (net purchased electricity) emission factors. In addition, t he emission factors reflect how

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40 using different fuels and different methods of attaining electricity can change the result of power plants, fuels, and use of cementitious materials help the industry reduce cement emissions by about 12 kgCO 2 /tonne of cement (24 lbCO 2 /short ton of cement) or about a 2% reduction. If purchased electricity was included in the cement emission factor the reduction is greater for Grasim, about a 7% percent difference. Also it might be important to note that if the functional unit was cementitious materials than Grasim shows a larger reduction in emissions. As stated previously the concrete emission fa ctor for India was also important. Currently no published research could be found regarding an emission factor for concrete in India. In the U.S. two studies have reported a thorough inventory for concrete production. The study by Reiner (2007) discusse s two different methods used to calculate a concrete emission factor. Using the software program Building for Environmental and Economic Sustainability (BEES) Version 3.0 Reiner estimated a concrete emission factor to be 0.17 tonnes CO 2 /tonne concrete. R on the BEES estimated concrete emission factor through the development of a life cycle analysis for concrete used in the city of Denver, Colorado. Through his LCA the concrete emission factor for a common type of concrete used in De nver (Class B) was estimated to be 0.22 tonne CO 2 /tonne of concrete. Reiner demonstrated that the concrete emission factor will vary due to the reality of different concrete mixture designs. The second study, contracted out by the U.S. Department of Ener gy (2003), calculated a concrete emission factor equal to about 0.15 tonne CO 2 /tonne concrete. Both studies by Reiner and the U.S. Department of Energy quantified concrete emission factors by gathering data from cement, aggregate, transportation, and re ady

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41 mixed operations. In India ready mixed concrete operations are not the commonly used method to produce concrete. As will be discussed in this chapter site mixed concrete is the main method of producing concrete in India. Throughout this chapter the development of a LCA (cradle to gate) for concrete will be discussed. Although 2 emissions it was decided by the author that a cement emission factor should be calculated to represent the majority of the companies that provide cement to concrete construction projects in Rajkot. The remaining sections in this chapter will discuss the energy consumption and efficiency methods being used by Indian cement manufacturing, the energy and CO 2 emissions for aggregate processing, transportation of materials, and on site mixing of concrete. Finally a concrete emission factor will be calculated for a conventional concrete mixture used in Rajkot, and for pervious and high volume fly ash concrete mi xture designs in order to show the environmental advantages of using pervious concrete and high volume fly ash concrete. 3. 2 Life Cycle Assessment of Cement and Concrete in India Tools such as an environmental life cycle assessment (LCA) can be used to a ssess certain environmental impacts (i.e. GHG emissions) that are associated with the different phases of a material or product. An LCA tool can also be applied as a strategy for determining how GHG emissions can be reduced to moderate the impacts of clim ate change. GHG are gases that trap heat in the atmosphere and are represented by global warming potentials (GWP) in CO 2 equivalents (CO 2 eq). Carbon dioxide (CO 2 ) is the baseline and has a global warming potential of 1; methane (CH 4 ) has a GWP = 21; and nitrous oxide (N 2 O) has a GWP = 310 (IPCC, 2007a). Chlorofluorocarbons (CFCs),

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42 hydrofluorocarbons (HFCs), hydrochlorofluorocarbons (HCFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6) have high GWPs and range from 90 to 23,900. The use o f concrete in urban areas of India ( i.e. Rajkot) is the focus for this dissertation. In this chapter CO 2 impacts are quantified for concrete such that the boundary of the LCA begins with the manufacture of cement up to the concrete production method used most commonly in cities in India (i.e. site mixed concrete). Insufficient literature exists on site mixed concrete, but this study will be one of the first to apply the method of LCA to site mixed concrete. In addition to the development of an appropriat e LCA model this chapter will show the CO 2 impacts of urban structural concrete mixture designs. These impacts will be compared to those calculated for previous concrete and high volume fly ash concrete to demonstrate the reduction in CO 2 that can be expe cted with the two sustainable concretes. An LCA takes into account energy, material inputs, and environmental releases from material acquisition, product manufacturing, transportation, use, maintenance, and disposal and/or recycling. In this disserta tion the impacts from a cradle to gate (resource extraction to the product leaving the manufacturing process) and the product use phase are quantified. The end of life of the product is not considered in this study. In a LCA study on high performance c oncrete Reiner (2007) describes three different models (process based, economy input/output [eio], and hybrid [combined process and eio]) used to complete an LCA. This dissertation uses the process based LCA model such that the inputs (materials and CO 2 e nergy resources) and the outputs (CO 2 emissions) are itemized for producing concrete in India. The following methodology was used to complete the LCA model:

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43 Goal and scope defined India is one of the largest producers of cement, however, not all the ceme nt companies follow the same protocol for determining CO 2 emissions. Therefore, within this study the process based LCA model will be used to quantify CO 2 emissions from fuel consumed in the cement manufacturing process. Calcining emissions that occur at the kiln will also be taken into account. The emissions from electricity are included from cement manufacturing as well. For the first the time an emission factor will be calculated for the production of site mixed concrete. This will also involve the emissions from fuel consumption during crushing of aggregate, transportation of aggregate, transportation of cement, transportation of fly ash, and operations of the portable cement mixer. The functional unit is one tonne of concrete Inventory analysis A description of the materials and processes used to make concrete is described throughout this chapter and the system boundary is shown in Figure 3.1 Impact Assessment The only greenhouse gas taken into account for the quantification of emissions is CO 2 The other five gases that can contribute to GHGs (methane, nitrous oxide, hydrofluorocarbons, sulfur hexafluoride, and perfluorocarbon) will not be included in this initial emissions study for Indian concrete. Normally these gases would be taken int o account but there is limited information on these gases for cement manufacturing in India and carbon dioxide emissions are usually more significant than the emissions from methane and nitrous oxide.

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44 Interpretation step The development of a model that can be used to determine the environmental impact of using a certain concrete mix ture design will be useful in understanding which alternative mix ture designs can provide the same serviceability and durability as well as reduce the environmental impac ts. environment, while the arrows represent the transportation used throughout the entire flow of materials. Figure 3.1 Life Cycle Phases and Material Flow for Concrete in Rajk ot 3.3 Understanding the Cement Production and Concrete Industry in India The production of cement is about a century old in India. The first cement industry was established in Porbundar, Gujarat in 1914 (DRPSCC, 2011). Table 3. 3 shows how India compa res within the top 19 cement producing countries/regions in the world for the year 2010. In 2010 India was the second largest produc er. In Figures 3. 2 and 3.3 the trend in cement production and potential cement consumption for four major cement producing countries are shown. Japan and India are unique in Figures 3 2 and 3.3 because Japan currently has the highest kiln capacity (3370 tonnes per day) and is first in energy efficiency while India is second in both categories. Despite, India being a major

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45 p roducer of cement the national per capita consumption is 0.136 which is lower than the world average which is about 0.48 and lower than that seen in China, U.S., and Japan (Refer to Figure 3. 2 and Table 3.3 ). However, India being one of the most populous countries and having an increasing economy have led the cement industry analysts to state that the slow increase in per capita cement consumption is just an indicator of the Manufa approximately 142 large cement plants together producing at least 161 million tonnes of cement a year. Two major companies ACC Ltd. And Ambuja Cements Ltd. withdrew membership from CMA thus there production is n tatistics presented in Table 3. 4 In fact during the 2009 2010 year Ambuja produced 20.1 million tonnes of cement while ACC Ltd. produced 21.4 million tonnes. The Indian cement industry has three types of cement units which are larg e, white and mini cement plants. The mini plants use vertical shaft kilns with cement production not exceeding 109,500 tonnes/year (120701 ton/year [ton = U.S. short ton]) and are plants that use the rotary kiln such that cement production does not excee d 300,000 tonnes/year (330690 ton/yr). Within this research the focus is pertaining to large cement plants. According to an article in the Indian Concrete Journal, concrete was identified as the preferred construction material in India (Kumar & Kaushik 2003). Between the years 1998 2003 major construction projects that utilized concrete were fly overs, metro rails, atomic and thermal power plants, road projects and the rebuilding of infrastructure in Gujarat after the destructive earthquake in January 2001. In 2002 concrete consumption in India was estimated at 190 million m 3 (249 million yd 3 ) A. K. Jain

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46 estimated that the rate of consumption of concrete should increase by at least 19.5 million m 3 (26 million yd 3 ) per year and ready mix ed concrete s hould account for 11.0 million m 3 (14 million yd 3 ) of the total concrete produced in India by 2012 (as cited in Kumar & Association (RMCMA) estimated that 20 to 25 million m 3 (26 to 33 million yd 3 ) of concrete were produced annually among 400 to 500 ready mix ed facilities (RMCMA, 2008). Although the ready mix ed concrete industry in India is growing, the ready mix ed concrete business in India is still emerging and only accounts for 5% of concrete consumed in India while the rest of concrete is site mixed. Table 3. 3 World Cement Production 2010 ( USGS, 2012 )

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47 Figure 3. 2 Trend in Cement Production for Four Leading Cement Producing Countries ( USGS, 2012; Parikh, Sharma, Kumasr, Vimal, IRADe, 2009) Figure 3. 3 Potential Trend i n Per Capita Cement Consumption f or Four Leading Cement Producing Countries ( USGS, 2012; Parikh, et al, 2009; United Nations 2010b)

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48 Table 3. 4 Indian Cement Industry Information ( CMA 2010a ; CMA 2010c ) 3.3 .1 Ready Mix ed Concrete Industry in India The first ready mix ed concrete batching plant was established in the city of Pune India in 1987. The batching plant closed shortly after being unable to meet the demands of large projects like the Tanji Wa di subway, which led to skepticism in the RMC market in India (Alimchandani, 2007; Gordon & Kshemendranath, 1999). The first succ essful ready mix concrete plant was ultimately set up 7 years after the Pune plant by ACC Ltd. (cement com pany) in Mumbai. Unitech Ltd. a nd RMC Group Plc soon followed with more ready mix ed plants in Mumbai. However even these RMC plants faced barriers because machinery and operations were not as sophisticated in comparison to plants established in Europe or South East Asia, agencies that could provide maintenance and technical support to plants were not well established in India, poor quality of aggr ega tes led to inconsistent mixtures the construction industry and contractors did not know how to schedule or plan for the use of ready mixed concrete, lack of specifications meant specifiers were reluct ant to recommend a product they were unfamiliar with, a nd there was need to invest in training a workforce (Gordon & Kshemendranath, 1999). Since 1994, the RMC industry has grown modestly. The perception of the RMC remains inconsistent since only a few companies have made the ready mixed industry their core

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49 business while others such as cement companies, who own RMC companies, think of it Kshemendranath). Today, most RMC plants are located in major cities such as Delhi, Ahmedaba d, Mumbai, Bangalore, Chennai, Kolkata, and Hyderabad where RMC a ccounts for 30 to 60% of total concrete used in the cities. To help encourage the growth of the RMC industry the RMCMA has been working towards guaranteeing quality RMC products through cert ification of plants around the country. 3. 3 .2 Site Mixed Concrete in India The advancement of the construction industry in India has been slow due to many factors. Historically, construction in India was heavily dependent on government funding for infra developing infrastructure in 1991. As a result of construction projects being subsidized by the government, timelines for completion of the projects were not enforced, bureaucra tic processes caused delays for construction, and the quality of construction projects was affected. Today, outdated construction techniques and specifications are still used. Site mixed concrete still uses portable concrete mixers, human chains and whee lbarrows to transport the concrete, concrete buckets are lifted by mechanical winch, and steel rods are still being used for consolidation and compaction of concrete instead of vibrators. Many RMC companies encourage the use of RMC over site mixed concret e a nd often list the following disadvantages of site mixed concrete (Gordon & Kshemendranath, 1999; Lafarge, 2012): The consistency and reliability of mixtures is dependent on the frequency of sampling and testing the variability of each mixture which is a lso dependent on

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50 the variability occurring with the manual mixing of individual proportions of 50 kg (110 lb) bags of cement The volume of concrete production within an 8 hour shift is dependent on the skills of the laborer. Manual mixing is more time consuming The quality of raw materials is manually checked or not checked at all Raw materials are often wasted More money is spent on time, effort and laborers Untrained and unskilled laborers create dangerous conditions and there is a lack of proper sup ervision Since materials are stored on site there is the likelihood that stock of materials can be stolen. Although, RMC companies make reasonable claims against site mixed concrete RMC is still 12 to 20% costlier than site mixed concrete. Additionally site mixed concrete is still the dominant method used in construction in India especially for rural and developing urban areas as was seen with the city of Rajkot. Site mixed concrete is a major source for employment opportunities. The inclusion of site mixed concrete in construction sector in 2000, thus employing 16% of the work force available in India. This is significant in comparison to a 6 to 8% employment of the working population in developed countries (The Indian Concrete Journal, 2004).

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51 3.3 .3 Indian Concrete Mixture Designs Specifications up until the year 2000 were still based on 1950s construction techniques and old British Standards such that struc tural concrete was based on M15 and M20 grades of concrete. The batching occurred by volume, thus meeting a certain nominal ratio by volume for each grade of concrete. This meant minimum strengths had to achieve 15 MPa (2176 psi) and 20 MPa (2901 psi) re spectively (Kumar & Kaushik, 2003; Gordon & Kshemendranath, 1999). Today these same mixture designs are commonly used for structural purposes in rural and developing urban areas. But as RMC concrete becomes more mainstream, specifications are revised to include more leeway for design mix ed concrete, the roles of aggregate properties are better understood, benefits are seen with lower water cement ratios, and with research and development showing improved concrete strength from lower cement contents new g rades of concrete (M20 through M40) have been adopted by public works departments. Large construction projects have been known to use M50 grade which is a form of high strength concrete, high performance concrete, compacted reinforced concrete, reactive p ower concrete, and self compacting concrete. High grades of concrete are often used in bridges, piles, high rises, and power plants (Kumar & Kaushik, 2003). The use of waste materials or byproducts has increased (i.e. ground granulated blast furnace slag metakaolin, and fly ash). Chapter 5 is dedicated to a discussion on fly ash use in Indian concrete. Table 3. 5 lists example mixture quantities for common grades of concrete in India.

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52 Table 3. 5 Mixture Proportions f or Typical Grades of Concrete (Ba sed on Saturated Surface Dry C onditions) (Kishore, 2012) Conversion to U.S. Customary units is 1 kg/m 3 = 1.686 lb/yd 3 3. 4 Cement Manufacturing Process in India The manufacturing of cement in India is similar to the process described in a report published by the Portland Cement Association which focused on the life cycle inventory of p ortland cement manufacturing in the United States (U.S.) (Marceau, Nisbet &Van Geem, 2010). The process u sed both in India and the U.S. is described in four major steps. Figure 3. 4 shows the four steps in cement manufacturing, previously described, for a cement company in India known as Grasim Industries Limited. 1. Limestone qua rries located near the cement plants are mined, drilled, and blasted to extract limestone. The limestone is crushed to approximately 5 cm (2 in) and stored for blending. 2. The limestone is proportioned with corrective raw materials in order to achieve the correct chemical composition. The materials are ground into a raw meal and stored in silos. Additionally any materials used for fuel (coal, wastes, petcoke and other alternative fuels) are processed, dried, and sized, blended and stored in silos onsite as well.

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Figure 3 4 Steps in cement manufacturing process at Grasim Industries Limited Cement Company (Grasim Industries Limited, 2008) Limestone Mines and Crushing Plant Limestone and Coal Stockpiles Clinker Loading Clinker Storage Cement Loading Cement Mill Cooler Kiln Pre Heater Raw Material Grinding 53

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54 3. The raw meal is fed into preheaters and then into the kiln systems. The fuel is fed into the kiln for combustion. High temperatures in the kiln help remove water from the raw meal, calcine the limestone, and cause necessary chemical reactions to form clinker. The clinker is cooled and stored before grinding. In the PCA report this stage is known as p yroprocess. 4. The clinker is moved from storage. It is ground to a fine powder with gypsum and performance enhancer to make Ordinary Portland Cement (OPC). Fly ash or slag can be a dded at this stage to make Port land Pozzolana Cement (PPC) and Slag Cement, respectively. Cement leaves the plant in 50 kg bags or in bulk. 3.4 .1 Phases of Cement Clinker The process of making p ortland cement involves firing calcareous material (i.e. lim estone, chalk, marl, and aragonite) with siliceous, argillaceous, and ferriferous ore materials (sand, shale, clay, and iron ore). The selection of raw materials is a meticulous process because high concentrations of trace elements can cause problems in t he plant or in the final product. There are four main phases (Alit, Belie, tricalcium aluminate alkali solid solution, and ferrite phase solid solution) in the OPC that form once raw materials have reacted. Ideally the chemical compositions that represen t these four phases are tricalcium silicate (3CaO.SiO 2 ), dicalcium silicate (2CaO.SiO 2 ), tricalcium aluminate (3CaO.Al 2 O 3 ), and calcium alumino ferrite (4CaO.Al 2 O 3 .Fe 2 O 3 ). These chemical compositions are often abbreviated as C 3 S, C 2 S, C 3 A, C 4 AF such that C = CaO, S = SiO 2 A = Al 2 O 3 and F = Fe 2 O 3 (Gani, 1997). A phase diagram (refer to Figure 3. 5 ) is best used to show how the relative proportions of the raw materials can direct the outcomes of

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55 the phases and microstructure of the clinker. In general, OPC should fall within a C 3 S, C 2 S, and C 3 A triangle in a phase diagram (Gani, 1997). Figure 3. 5 Phase Diagram for Ordinary Portland Cement ( Gani, 1997) 3.4 .2 Kilns The kiln plays an important role in contributing to the structure of the clinker and form ing the final product. High temperatures are required to form the complex mixture of the clinker. The flame of the burner is approximately 2000 o C (3632 o F), the material making up the clinker has minimum temperature of 1455 o C (2610 o F), and precalciners ar e between 1000 o C (1832 o F) and 1200 o C (2192 o F) (WBCSD, 2005b; Gani, 1997). The kiln is usually a large steel tube lined with refractory (i.e. bricks) and is inclined by about 3 o to 5 o from horizontal. The kiln rotates slowly (20 to 86 rph) as the raw mate rials are fed into the top of the kiln. There are three main types of processes used in the production of cement with a rotary kiln: wet, semi dry, and dry process. In India between

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56 2009 and 2010, 97.9% of cement produced by large plants was a result of using the dry process, 0.5% of cement production was completed by the wet process, and 1.6% of cement production was a result of other processes (CMA, 2010a). Within the wet process the raw materials are fed into the kiln as slurry with 37% 39% moisture d ue to being mixed with water. In the semi dry process the raw material has 10% 15% moisture and is partially calcined before entering the kiln. In the dry process the raw material is fed into the kiln as a dry powder. Cyclone heat exchangers and precalc iners located before the kiln use the hot gases from the kiln to dry and partially calcine the raw materials. If precalcined, in addition to dried and preheated, the production rate in the cement kiln can be increased by 50% to 70%. To accomplish precalc in ing a burner is constructed between the kiln and the preheating cyclones. Precalcining can help extend the life of the refractory by reducing some of the heating load that is required in the kiln (Gani, 1997). 3.5 Energy Consumption within the Cement Industry The production of cement is an energy intensive process. Particularly in step 3, of the cement manufacturing process, it was noted that high temperatures are required in the kiln. The traditional kiln fuels burned (coal, petroleum coke, sometimes natural gas, and fuel oil) result in an energy consumption between 3000 and 6500 MJ of fuel/tonne of clinker (depending on the manufacturing process) (WBCSD, 2005b). Grinding and milling are typically dependent on e lectricity and the pyroprocess might use electricity. Purchased electricity consumption can amount to 0.52 million Btu/tonne of cement (153 kWh/ton of cement) (U.S. DOE, 2003). However, the global cement industry has the opportunity to increase efficienc y by 0.2% to 0.5% per year, by replacing outdated

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57 equipment, converting to the dry process, and focusing on mineral and energy recovery through use of wastes and by products (WBCSD, 2005b). 3.5.1 Energy S cenario in the Indian Cement Industry Indian indust ries such as steel, aluminum, and cement account for the largest share in the demand for commercial energy. In 2007 industries had a 44.8% share in the total energy consumption for India. The industry share could be further broken down into cement accou nting for 13.5%, aluminum 11.4%, steel 39.7%, and others 35.4% (Dutta & Mukherjee, 2010). The Indian cement industry is the second largest producer of industry. Average ki ln capacity is 2860 tonnes per day (3152 ton per day) which is 510 industry has made significant modifications to the process in order to reduce the energy intensity. Tech nological upgrades have resulted in an average thermal energy consumption of 725 kCal/kg of clinker (2.6 million Btu/ton) and an average electricity consumption of 82 kWh/tonne of cement (0.3 million Btu/tonne) which is about 75 kCal/kg of clinker (0.3 mil lion Btu/ton) and 17 kWh/tonne (0.05 million Btu/ton) of cement more than that recorded for the best performing plant in the world (DRPSCC, 2011; CMA 2010a). In Table 3. 6 energy use between India and the U.S. is compared. Between 2009 and 2010 Table 3. 6 s hows that the U.S. cement industries operated with lower energy efficiency than Indian cement industries. Additionally, India produced more clinker and cement while achieving lower energy intensities in that same year. As mentioned previously, India has invested in operational efficiency, process control, and energy conservation by use of alternative raw materials and fuels, waste heat recovery

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58 systems/cogeneration systems, captive power plants, and higher productions of blended cement. Table 3 6 Avera ge Energy Use Between India and U S Cement Industry for 2009 2010 Source India: ( DRPSCC, 2011; CMA, 2010a ) Source U.S.: ( Marceau, Nisbet, & VanGeem, 2010; USGS, 2011 ) 3.5 .2 Methods of Energy Efficiency As seen in Table 3. 6 the electricity used (per tonne of cement) by Indian cement industries was about 57% of what the U.S. used. In order to avoid purchase d electricity, Indian cement industries have established captive power plants (CPPs) on site, where cement manufacturing occurs. Within 2002 and 2 004 the installed capacity of captive Nag, Yajnik, Heller, & Victor, 2004). A common reason for the growth in CPPs was the advantage of having uninterrupted power for industrial processes. Unlike many of the power generation utilities for the country the CPPs are owned by the industries and not the government. However, in states such as Gujarat, permission to set up a CPP has to be attained from the Gujarat Electrici ty Board. The size of the CPPs can vary, for example, was 0.088 MW and the largest was 240 MW. The fuels that are commonly used in a CPP include lignite, coal, fuel oil, light diesel oil, high speed diesel, naptha, natural gas, and bagasse (fibers left from sugarcane). Cement industries are typical consumers of coal,

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59 gas, and naptha and the typical sizes of the CPPs are medium (30 MW capacity) to large (above 50 MW capacity) (Shukla et al., 2004; Ambuja Cements Ltd, 2010). Many industries that use CPPs use the plants as backups but within the cement industry the CPPs provide the main advantage of a reduced cost in generation compared to tariffs established for industries by state utilities (Shukla, et al., 2004). Between 2009 and 2010 59% of cement production in India was achieved with captive power plants. Another method of reducing energy demand within the cement manufacturing process is to use the method of waste heat recovery. Waste heat recovery leads to a reduction in fuel consumption which in turn could reduce the size requirements for the equipment needed for the waste heat recovery system and reduce emissions from combustion of fuels Waste heat recovery systems in cement plants utilize hot gases for electricity production (also known as co generation) or it can be used for preheating the raw material. Most waste heat from dry process cement kilns are within a temperature range of 62 0 730 o C (1148 1346 o F) which is considered a medium temperature range (230 650 o C [450 1200 o F]) for waste heat recovery (BCS Incorporated, 2008). Preheating is the most common form of waste heat recovery and is accomplished by absorbing the waste heat from kilns and transferring the heat to the raw meal through 6 to 4 stage cyclones that are located before the kiln ( Refer to Figure 3.4). The efficiency of power generation depends on the temperature of the waste heat. Thus traditional waste heat recovery te chnologies need medium to high temperatures to produce power. To power an electric generator from waste heat, this can involve heating boilers to generate steam that turns a turbine. For cement kilns other technologies besides the traditional waste heat t o boilers are being explored. These technologies

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60 include organic Rankine and Kalina cycles. These technologies are being considered because they work more efficiently even with low to medium gas exhaust temperatures. The organic Rankine cycle uses an or ganic fluid (i.e. silicon oil, propane, isobutene, etc.) instead of steam with a higher molecular mass (desired for compact designs) and high mass flow to turn a turbine which will generate electricity. The Kalina cycle is similar to the Rankine cycle exc ept it involves the use of ammonia and water as the working fluid. The combined use of fluids is called a binary fluid. Binary fluids can achieve greater efficiency because the boiling points of ammonia and water are different, therefore concentrations c an be varied to attain more specific temperatures. Also, standard steam turbine components can be used if ammonia and water are used in a waste heat recovery system because both molecular weights (ammonia = 17.03 and water = 18.01) similar to steam so sta ndard steam turbine components can be used in the waste heat recovery system (Mirolli, 2005; BCS Incorporated, 2008). Figure 3. 6 Cyclone Heat Exchangers and Precalciner ( Gani, 1997)

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61 Use of by products and/or waste as fuels reduces the cement industrie 2 emissions. Hazardous and non hazardous materials are sources of energy and can be used for fuel in cement kilns. The practice of using waste and by products from other industries to crea te a closed loop for resource use is also known as waste co processing. This practice has been common among cement manufacturing industries in some parts of the world for more than 20 years and is considered a method for waste management (i.e. Norway) (WB CSD, 2005b). To encourage safe and sustainable use of waste materials the Cement Sustainability Initiative established by the World Business Council for Sustainable Development has developed a document that provides guidance on the selection of fuels and raw materials for the cement manufacturing process (WBCSD, 2005b). Types of alternative fuels are listed in Table 3. 7 However, the selection process for using alternative fuels depends on certain parameters, besides health, safety, and environmental con siderations, which must be evaluated. For example, the assessment should be based on chlorine, sulfur, and alkali content (these constituents can clog the kiln system), water content, heat value, and ash content (ash content affects the chemical compositi on of the clinker). Any by product or waste material must be introduced at the correct point in the cement manufacturing process in order to avoid unwanted emissions or changes in the necessary chemical composition of the clinker (WBCSD, 2005b).

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62 Table 3 7 Examples of Non Hazardous and Hazardous Alternative Fuels ( WBCSD, 2005b ) 3.6 Management, Energy Efficiency Ventures, and Emission Trends for Indian Cement Companies Understanding how the companies are managed can also explain why the Indi an cement industry consumes less energy and still be able to produce more cement per year in comparison to a country like the U.S. (where Table 3. 6 shows the differences in cement production). Periodically, cement companies in India will restructure and consolidate. For example, Gujarat Ambuja Cements Ltd. has a 14% stake in ACC Limited, Grasim Industries Limited acquired controlling stake over UltraTech in 2004, then Grasim vested with Samruddhi Cement in 2010 and finally merged with UltraTech (UltraTec h, 2012; Dutta & Mukherjee, 2010). Additionally the Indian cement industry comprises of some overseas investors. Stakes in Indian cement companies have been Holcim (ent ered with Gujarat Ambuja) (Dutta & Mukherjee, 2010). Advantages of merging and reorganization of cement companies in India have evolved into the following: opportunity for the company to be highly competitive, have access to new

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63 markets, and pursue cost e ffective and energy efficient technologies (Dutta & Mukherjee, 2010). 3.6.1 Energy Efficiency and Embodied in Cement Manufacturing in India T (2010a) from 2006 through 2010 indicated that companies collaborated with th e State Pollution Control Board and GTZ German Technology Corporation on trials of using waste derived fuels. The results of such collaboration led to recommendations for recycling hazardous wastes such as tires, paint sludge, petroleum tar waste, and eff luent treatment plant sludge in the cement kiln. Cement companies such as Ambuja Cements received awards (such as the 2010 Green Tech Gold Environment Excellence Award and the 2010 National Award for Excellence in Water Management Award) emphasizing the c technologies. Ambuja has also indicated that 70% of total power requirement in 2011 was indicated that a 1 million tonne cement plant would need about a 20 MW of power capacity and according to the Grasim Sustainability Report a combined capacity of 144 MW captive power plants are located at four sites. So it might be assumed that on site captive power plant capacity could range between 1 MW to 40 MW depending on the capacity of cement production (Ramakrishnan, 2012 & Grasim Industries Ltd., 2008). India Cements Company has an 8 MW waste heat recovery plant. ACC Ltd. Cement Company uses captive power to meet 72% of its power requiremen t (Ramakrishnan, 2012). Grasim Industries began utilizing hazardous waste in kilns since 2007 2008 and reported that 1,400 tonnes of coal was replaced with 2,823 tonnes of hazardous waste between 2007 and 2008. Grasim has setup a municipal solid waste pr ocessing plant such

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64 that the processed waste used as alternative fuel in 2007 was 7126 tonnes. Between 2007 and 2008 Grasim received the Energy Conservation Award and the Greentech Silver Award for reductions in dust emissions. Grasim was one of the earl iest users of the rankine cycle technology for waste heat recovery (Grasim Industries Limited, 2008). Within the annual reports prepared by the individual companies information about how the company conserved energy or upgraded equipment within plants is reported. Understanding technological upgrade and methods of generating energy and fuel use within the Indian cement industry was important for this study in order to verify or calculate a cement emission factor. As will be explained in the section pe rtaining to the life cycle analysis (LCA) of cement a cement emission factor had been calculated by a few organizations or entities within the country of India, however, these emission factors did not agree with one an other. Therefore, as part of this stu dy it became pertinent to perform a bottom up approach to calculate or verify the Indian cement emission factor which required a little more in depth knowledge about individual companies. Since, the case study involved the city of Rajkot the Indian cemen t companies that were located in Gujarat were used for the performance of the LCA. According to the CMA (2010c) between 2009 and 2010 there were at least eight different member companies that had plants in the state of Gujarat. Three of the member compa nies (Gujarat Sidhee Cement, Saurashtra Cement [known as the brand Hathi] and Ultratech Cement Ltd.) and two non member companies (Grasim Industries and Ambuja Cements Ltd.) were chosen for the LCA study.

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65 3.6 .2 Emission Trends in Cement Manufacturing in India GHG emissions have been associated with the charge of contributing to climate change. As stated previously the importance of quantifying these emissions leads to comprehension of material use and embodied energy of these materials. Finally, methods for reducing emissions depend on revolutionizing the way materials are used and modifying the embodied energy associated with the materials. Total emissions can be calculated by multiplying an emission factor (EF) by the total amount of activity or production of a material. The EF or emission intensity is the rate of a pollutant or gas relative to the activity or production of material (IPCC, 1996). The CO 2 emissions from the production of cement are a function of two processes: calcining and the combustion of fuel. Calcining is the process when the raw material chemically changes wh en reaching extremely hot temperatures. In other words when heating the calcium carbonate (CaCO 3 ), coming from calcium rich materials (i .e. limestone), calcium oxide (CaO) and carbon dioxide (CO 2 ) form (see also Equation 3.1) (3.1) Estimation of CO 2 emissions from calcining is a function of the lime (CaO) percentage (content) for clinker. In the IPCC 1996 guidelines the default lime content was estimated at 0.646. Lime percentages vary little between cement plants so if lime content is unknown the IPCC default factor is often used (W BCSD, 2005a). Lime content can result from other materials such as f ly ash and not from the calcium carbonate. If that is the case this percentage of lime content should be subtracted out of the total lime content before calculating the calcining emission factor (IPCC, 2006). The lime content is multiplied by the molecul ar weight ratio for CO 2 /CaO (44.01 g/mole 56.08 g/mole =

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66 0.785) to calculate tonnes of CO 2 /tonne of clinker. Thus the emission factor (EF) for calcining, in reference to clinker produced, is 0.507 tonnes CO 2 /tonne of clinker (IPCC, 1996). In the 2006 I PCC guidelines a correction factor for cement kiln dust (CKD) was incorporated into the calcining emission factor. CO 2 can result from lost CKD and can range between 1.5 and 20% for a cement plant. If no information is available on CKD the default factor recommended by IPCC (2006), is 1.02. The 0.507 tonnes CO 2 /tonne of clinker factor is multiplied by the CKD correction factor (See Equation 3.2. The corrected calcining emission factor is 0.517 tonnes CO 2 /tonne of clinker. EF clinker = lime content mo lecular weight of CO 2 /CaO CKD correction factor EF clinker = 0.646 0.785 1.02 EF clinker = 0.517 tonnes CO 2 /tonne of clinker (3.2) The general methodology for estimating emissions from the combustion of fuel and electric it y used requires the knowledge of the total amount of fuel or energy used in the process, and the emission factor that relates the rate of CO 2 released per amount of fuel combusted or electricity used. The amount of fuel used in the process can be reported as total volume, mass, or ene rgy. Additionally, the emission factor can be reported as rate of CO 2 released relative to energy associated with the fuel combusted. In these cases the calorific value (i.e. kcal/ kg) and density of the fuel (kg/m 3 ) is needed in order to derive a final emissions factor in the form of tonnes of CO 2 per tonne of cement produced. T his study involves the calculation of an emission factor for cement, but the cement companies have established cement emission factors. However, recent (years

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67 2007 2010) emission factors, even if for the same year, vary between 0.65 0.83 tonne CO 2 /tonne of cement material (Refer to Figure 3. 7 ). From Figure 3. 7 there is a downward tren d in emissions starting from 1996 to 2010. The decrease in emissions is best explained by the upgrade of equipment for energy efficiency, the use of captive power, cogeneration, clinker substitution (with raw materials such as fly ash and slag), and wind power generation (CMA, 2010a). Sources: A Schumacher, Sathaye, 1999; B Hendricks, Worell, de Jager, Blok, Riemer, 2004; C Parikh, Sharma, Kumar, Vimal, IRADe, 2009; D CCAP, TERI, 2006; E Garg, Shukla, Kaphse, 2006; F MoEF, 2010; G CMA, 20 10a; H WBCSD, 2010 Figure 3.7 Indian Cement Emission Factors f or 1991 2010 Emission facto rs reported in 2006 and 2007 were a result of the CMA taking part in a two phase project, under the Ministry of Environment (MoEF) and Forests and United Nations Fr amework Convention on Climate Change (UNFCCC), titled NATCOM (National Communication). The project involved annualizing GHG emissions for developing countries who were participants in the Kyoto Protocol. The CMA gathered data to calculate emissions from 119 major plants out of 136 in 2007 (this was

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68 approximately a 88% response to a questionnaire of questions sent out to the companies). During the process for gathering data for emissions the CMA encountered certain problems. For example, many of the maj or companies (their capacity accounted for 40% of the total capacity of the country) were not CMA members and had chosen to report emissions using the system affiliated with the Cement Sustainability Initiative established by the World Business Council on Sustainable Development. These companies included Grasim Industries [now under UltraTech], ACC Ltd., and Ambuja Cements Ltd. In Figure 3.7 for the years 2007 through 2010, individual cement companies had volunteered to report company emissions through th e Cement Sustainability Initiative (CSI), Both CMA and CSI follow IPCC guidelines; however, according to the CMA there are some differences between CMA and CSI in their process for emissions calculations which were not explained. Upon review of the guide lines by CSI the use by many companies around the world so only default emission factors listed in IPCC and a few CSI calculated emission factors are listed in th e guidelines. It is possible the cement companies in India who are working under the CSI protocol may have not used country specific emission factors for fuel as has been done by the MoEF and CMA. A list of fuel and electricity emission factors is shown in the Appendix as Table B.1 The purpose of Table B.1 is to show users how important it is to research the correct fuel emission factor because often a fuel may be called something different between countries but is essentially the same fuel or sometimes the fuel emission factor can be updated every few years. Additionally, in order to create Table B.1 it involved an intensive literature review. At the time of the study there was not a well established database of

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69 country specific emission factors. Cur rent comprehensive online emission factor databases or up to date life cycle inventory data are not free and require the user to pay a certain fee. Such databases include http://www.ecoinvent.org/ and http://emissionfactors.com/ Calcining emission factors can differ and Table 3.8 shows some ex amples. CSI provides guidance to companies on how to calculate CO 2 emissions from calcination of clinker, dust, and carbon from raw materials. The guidelines specifically encourage companies to measure calcium Oxide (CaO) and magnesium oxide MgO contents of clinker at the plant level (WBCSD, 2005a). These measurements can give a more precise emi tonnes CO 2 /tonne of clinker. Grasim, in their 2007 2008 sustainability report, calculated CMA also calculated their own calcining emission factor (which includes a CKD factor) as 0.537 tonnes CO 2 /tonnes clinker produced. The values reported by GRASIM and th CO2/tonne of clinker would be used in the life cycle analysis. Table 3. 8 Example Differences in Calcining Emission Coefficients Note: Grasim actually reported a calcining emiss ion factor of 0.427 tonnes CO 2 /tonne of cement The Grasim sustainability report, however, did not show total clinker produced,

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70 thus a cement/clinker ratio was assumed based on the industry average for the year 2007 2008 in order to conver t to tonne CO 2 /t onne of clinker. The industry average for cement/clinker ratio was 1.45 and for a company like UltraTech (who merged with Grasim) its ratio was 1.14. So the average between the two ratios (1.3) was used in order to calculate calcining emissions for Grasim (Source: http://content.icicidirect.com/mailimages/Ultra_tech final.pdf ) 3.7 Materials Fuels, and Emissions Associated with Cement and Concrete 3.7 .1 Cemen t individual companies through the CSI it was uncertain which was most representative of the Indian cement industry. Observations of cement use in Rajkot led to the decision to deter mine a cement emission factor based on frequently used brands of cement in Rajkot. The brands included Ambuja Cement Ltd., UltraTech Cement Limited, Gujarat Sidhee Cement Limited, Hathi Cement (brand name under flagship company Saurashtra Cement Limited). of data was gathered either for 2009 2010 or 2010 2011 regarding the electricity purchased, total energy used from coal, total volume of certain fuels and oils, total clinker pro duced, and total cement produced. Typical data gathered from the annual reports are shown in Figure B.1 in Appendix B. Th e annual reports provided the opportunity to determine which companies were taking advantage of certain technologies ( as discussed in Section 3.4 .2) that made the manufacturing process more energy efficient. Table 3. 9 lists all the raw data gathered from the four companies. The clinker/cement ratio was calculated from the production of cement and clinker that was report ed on the annual reports. From Table 3.9 it is important to note that all companies reduced the depende nce on grid electricity through the use of captive power plants. Major companies such as UltraTech showed the use of waste heat recovery.

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Table 3.9 F uel and E lectricity Raw Data Gathered f or Calcul ation of Cement Emission Factor 71

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72 The electricity and fuel data was converted to total CO 2 emissions using country specific emission factors available from various sources listed in Table 3. 10 As seen in Table 3.9 not all the fuel information was recorded in terms of energy. For the fuels that were recorded in units of volume, information such as calorific value of the fuel and density of the fuel were required. The calorific val ues are included in Table 3. 10 and density values are shown in Table 3. 11 An average density was calculated within each range shown in Table 3. 11 and was used in the calculations for total CO 2 from the fuel used. The equations below are shown to clarify the process used to determine the unit mass of CO 2 from total fuel used in the cement manufacturing process for the year. Note: All fuel for on site transportation was assumed to be included in the data provided in the annual reports. If transportation energy use was not reported as part of the annual reports then according to the study performed by Marceau, Nisbet, and VanGeem (2010) we can assume transportation energy contributes about 2% of total energy input. Marceau, Nisbet, and VanGeem calculated an average of 0.091GJ/tonne of cement (39.1Btu/lb cement) and 3.2 kgCO 2 /tonne of cement (6.41 lb of CO 2 /ton of cement) from transportation.

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73 Table 3. 10 Country Specific Emission Factors Used in Calculating a Cement Emission Factor 1 kg CO 2 /kWh = 646 lb/MBtu Table 3. 11 Density Values for Certain Fuels Used i n Indian Cement Manufacturing 1 kg/m 3 = 0.062 lb/in 3

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74 Tables 3.1 2 through 3.1 9 demonstrate how the energy reported in the annual reports were converted into total emissions. Energy is considered the material flow analysis portion while the emissions factor for each type of fuel used for energy is conisdered the life cycle analysis results. Finally MFA multiplied by LCA results into total impact or total emissions from the energy produced from the fuel. Table 3.1 2 MFA LCA Data f or Purchased Electricity Table 3.1 3 MFA LCA Data f or Company Generated Electricity from Coal Table 3 .1 4 MFA LCA Data f or Company Generated Electricity from LDO / Furnace Oil

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75 Table 3.1 5 MFA LCA Data f or Company Generated Electricity from Natural Gas Table 3.1 6 MFA LCA Data f or Thermal Energy from Coal Table 3.1 7 MFA LCA Data f or Thermal Energy from Light Diesel Table 3.1 8 MFA LCA Data f or Thermal Energy from Furnace Oil

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76 Table 3.1 9 MFA LCA Data f or Thermal Energy from High Speed Diesel Oil Table 3. 20 shows the total production of cement for a given year for each company. Table 3. 20 Cement Production f rom Major Cement Manufacturing Companies t hat Deliver t o Rajkot India 3.7.1.1 Overall Result Table 3. 21 and Table 3.22 show the results of energy use and CO 2 emissions arising from the fuels and electricity per unit production of cement. The calculations were based on four major cement companies that have plants located in Gujarat and provide cement to city projects based in Rajkot, India. From Tables 3. 9 and 3.22 the data revealed that Ambuja and UltraTech are the larger producers of cement and total CO 2 emissions. All companies do use captive power plants to save on costs spent on purchased electricity either by generating electricity thr ough fuel oils and coal (Refer to Table 3.9 ). Companies such as Ambuja and UltraTech appear to be using natural gas as well (Ambuja, 2010; UltraTech, 2011; and Shukla et al., 2004). UltraTech in particular reported some energy savings through the use of waste heat recover y. The savings totaled about 0.002GJ/tonne of cement (1.2 Btu/lb of cement). Finally averaging the four main Gujarat cement producing companies revealed that the average cement emiss ion factor is approximately 0.84 tonnes CO 2 /tonne of cement (1 680 lb CO 2 / short

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77 ton of cement) when excluding purchased electricity emissions. This average is closer to the emission factor reported by CMA (2010a) for the year 2007. Table 3. 21 Energy Consumption f rom Major Cement Manufa cturing Companies that Deliver t o Ra jkot India Net purchased electricity 1 GJ/Tonne of cement = 429.92 Btu/lb of cement, 1 kWh/Tonne of cement = 1.54 Btu/lb, 1 tonne/tonne = 2000 lb/short ton = 1000 kg/tonne 3.7.1.2 Company to Company Comparison From Table 3.21 key cement producers such as Ambuja might be expected to produce more CO 2 per tonne of cement since the industry uses more energy from both thermal and purchased electricity sources at least compared to Sidhee and Hathi. However, once the energy is calc ulated per unit mass of cement and converted to CO 2 per tonne of cement a large cement producer such as Ambuja demonstrates that it has taken certain measures to reduce energy consumption and CO 2 emissions for the large amounts of cement that they produce In the annual reports, reduction in CO 2 is not discussed, however, details on energy conservation are required to be listed as per Section 217 (1) (e) of the Companies Act, 1956 (Ambuja Cements Ltd., 2010). Energy saving methods

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78 were discussed earlier in this chapter and Ambuja uses so me of these methods as listed in their annual report. These methods include optimization and upgrading the process and equipment (replacing pre heaters, shortening the chamber for the cement mill), adjusting operating vol tage for lights, installing alternate fuel system lines, and installation of more captive power plants. Although, Ambuja is using waste derived fuels and has an alternative fuels and raw material (AFR) testing laboratory, the amount of waste used as fuel i not include the amount of alternative waste fuel used. Any additional CO 2 coming from waste fuels is not being included in the calculation of the cement emissions fact or so the emissions factor might be underestimated in this dissertation. However, we might assume that the alternative waste fuels may not contribute more than say 5 % of total CO 2 Fossil fuels are still dominant in the entire cement process and this cou ld be a valid assumption because, if we recall that Grasim seemed to be the first to provide a thorough alternative waste fuels contributed about 0.6% to the total CO 2 emissi ons reported from kiln fuels for Grasim. It is also important to note that Grasim, ACC Ltd., and Ambuja were the companies that had th e largest share in the industry Therefore, it should be safe to assume that all other comp alternative waste fuels were 0.6% or less of total CO 2 emissions. This percentage should not greatly change the calc ulations presented in Table 3.22

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79 Table 3 .2 2 Emissions f rom Major Cement Manufacturing Companies that Deliver t o Rajkot India 1 kg/t onne = 0.001 tonne/tonne 1 tonne/tonne = 2000 lb/short ton = 1000 kg/tonne 3.7.1.3 Cementitious Materials Additionally, Ambuja, as well as the other three companies, use fly ash and slag to produce blended cements and thus re duce the amount of clinker that is needed in the process, which leads to fewer CO 2 emissions. Not all companies reported the amount of slag u sed for the year so in Table 3.2 3 only the amount of fly ash used for the year 2009 2010 or 2010 2011 is shown. Ambuja uses fly ash equal to about a quarter of how much cement is produced, UltraTech uses an amount of fly ash that is at least 15% of the cement produced and the other two c ompanies use of fly ash between 4 and 5% of the amount of cement they produce.

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80 Table 3.2 3 Fly Ash Consumption by Major Cement Companies w ho Deliver t o Rajkot India 3.7.1.4 Energy Intensity Recall in Table 3.6 the average energy intensity for cement manufacturing in was shown. The fuel energy intensity according to the CMA is including only fuels used for firing the kiln while t he electricity intensity is including the purchased and onsite calculating the fuels needed for on site electricity the total amount of fuel did not match the amount of fuels reported in the annual reports. So the energy reported for on site generation was converted into CO 2 emissions using each of the fuel emission factors reported in Table 3.9 and included efficiency for coal, oil, and natural gas captive power plants. The efficiency of the captive power plants were taken from a report written by CCAP and TERI (2006) where coal was 30% efficient, oil was 32% efficient, and natural gas was 39% efficient. Thermal energy reported in T able 3.21 can be compared to Table 3.6 If the energy in Table 3.21 is converted using the clinker ce ment ratio reported in Table 3.9 the values would change such that Ambuja = 3.1 GJ/tonne of clinker (134 4 Btu/lb of clinker), UltraTech = 3.2 GJ/tonne of clinker (1359 Btu/lb of clinker), Sidhee = 3.4 GJ/tonne of clinker (1444 Bt u/lb of clinker) and Hathi = 3.3 GJ/tonne of clinker (1438 Btu/lb of clinker). All cement companies report a slightly higher therm al energy intensity compared to t he average reported in Table 3.6 for India Electricity intensity

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81 was reported in t he annual reports (See Table 3.9 ), however, trying to recalculate this same intensity using the values available from the report resulted i n different electricity inensi ties as can be seen in Table 3.21 It is possible that the electricity reported in the annual reports included electricity used for colonies (or the people and villages that live on site or next to the cement manufacturing pl ants). Nevertheless, using the electricity i ntensities reported in Table 3.21 (Own + Purchased) it can be seen that all cement companies use more electricity per tonne of cement compared to the average repo rted in Table 3.6 with the exception that Amubja and Sidhee electricity intensities being only 7 kwh/tonne of cement (10.8 Btu/lb of cement) more than the average. 3.7.1.5 CO 2 Emissions Factor Conclusion From Table 3.2 2 companies, such as Sidhee and Hathi, whose production is only 8% to 9% of the pro duction o f Ambuja produce a maximum of 63 % more tonnes of CO 2 /tonne of cement compared to Ambuja. It is worth noting that Sidhee appears to still be heavily reliant on purchased electricity compared to Hathi. Although Hathi purchases less electricity, the resulting total tonne of CO 2 emissions per tonne of ceme nt is about 13 % higher than Sidhee assuming all cement manufacturing companies share the same calcining emissions. UltraTec h and Ambuja show emission facto rs lower than Grasim (refer back to Table 3.2). This confirms that Ambuja, UltraTech, and Grasim ar e still leaders in investing in energy efficient and CO 2 reducing methods. Although all this dissertation proves that it was necessary to go through the process of calculating a c ement emission factor for at least Gujarat, India and clarify where the cement manufacturing

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82 process stands in India in terms of CO 2 emissions as compared to the variou s emis sion factors shown in Figure 3.7 3. 7 .2 Quarrying and Mining of Other Raw Materi als (Excluding L imestone) Limestone is quarried onsite where cement is manufactured. However, its not clear whether raw materials (sand, gypsum, clay) included in the cement process are mined on site or off site. Table 3.2 4 shows the amount of materia l mined or quarried and the total emissions from the equipment used in the process. Off site informatio n was used to determine an emission factor for quarrying and mining thes e raw materials. cement manufacturing uses approxim ately 0.45 tonne of raw material/tonne cement. Therefore, the EF for quarry and mining becomes 0.0009 tonne CO 2 /tonne cement. Table 3.2 4 Production a nd Emissions From Quarry a nd Mining Production and Emissions Source: MoEF, FIMI, & Rauy and Reddy Production of material( million tonnes) 703.1 Total CO2 (tonnes) 1.46 EF (tonnes CO2/tonne material) 0.002 3.7 .3 Coarse and Fine Aggregate Crushing. A report from the Central Pollution Control Board (2009) was used to calculated emissions for aggregate crushing. This report appears to be the only available report on aggregate crushing and it specifically focuses on stone crushers in Gujarat. The foll owing labels are used to indentify coarse to fine aggregate sizes. Coarse Aggregate Black Trap (Metal or Kappchi) Fine Aggregate Black Trap (Grit or Dust)

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83 Stone crusheres range from large to small. Large usually produce greater than 100 tonne/hr (T PH) while small stone crushers produce 25 TPH. Stone crushing is higly labor intensive such that breaking, feeding, retrieving, and stockpiling are all performed manually. Table 3.2 5 shows the final fuel/energy emission factors calculated for stone crus hing. Table 3.2 5 : Emission Factors f or Aggregate Crushing Fuel or Energy Emissions Electricity (tonne CO 2 /tonne stone) 0.002 Diesel (tonne CO 2 /tonne stone) 0.0001 3.7 .4 Tranpsportation of Materials The assumption was made that all materials will be delivered by freight vehicles which are usually 3 axle trucks. For cement transportation the sources on emissions were gathered from Mckinsey and Company, 2010; Zhou, McNeil, 2009; and CMA, 2010. Fore aggregate transport the sources on emissions were granthered from Zhou, McNeil, 2009; Reddy & Jagadish, 2003. Sources for fly ash transportation included Zhou, McNeil, 2009; Redd y & Jagadish, 2003. Tables 3.2 6 through 3.2 8 lists the emission factors for cement, aggregate and fly ash transportation and average distances travelled. Table 3.2 6 Emission Factors a nd Average Distance Travelled f or Cement Transportation Cement Transportation Average kg CO 2 /tonne km Average Distance T ravelled (km) tonne CO 2 /tonne Truck (Diesel) 0.14 280 0.04 Rail (Diesel) 0.008 577 0.005 Sea (Diesel) 0.014 900 0.01

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84 Table 3.2 7 E mission Factors and Average Distance Travelled f or Transport o f Aggregate. Aggregate Transportation Average kg CO 2 /tonne km Average Distance Travelled (km) tonne CO 2 /tonne Truck (Diesel) 0.14 75 0.01 Table 3.2 8 E mission Factors and Average Distance Travelled f or Transport o f Fly Ash Fly Ash (Truck) Transportation Average kg CO 2 /tonne km Average Distance Travelled (km) tonne CO 2 /tonne Vanakbori 0.14 302 0.04 Gandhinagar 0.14 258 0.035 Sikka 0.14 119.5 0.016 3.7.5 On site M ix ed Concrete The concrete mixer is usually located on site where construction is occuring. The concrete mixer usually has a mechanical hopper attached as shown in Figure 3. 8 Specifications regarding these types of concr et mixers are shown in Table 3.2 9 which was gathered from various manufacturer specifications Figure 3. 8 Concrete Mixer w ith Mechanical Hopper

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85 Table 3. 2 9 Specifications of Concrete Mixer Specifications Units 5 kW diesel engine 7 Average Productivity m 3 /h Using the following equation the emission factor for can be calculated. The diesel emission factor was previously listed. Final emission factor was equal to about 0.00008 tonne CO 2 /tonne concrete. Information regarding specifications were gathered from various dealers. 3. 7 .6 Summary of Life Cycle Inventories A summary of emission factors are shown in Ta ble 3. 30 The largest contributing emission factor is arising from cement manufacturing. If the emission factors were compared to Reiners calculations for Ready Mixed concrete in Table 3. 31 Indian on site concrete mixing has lower emissions. Reiner reports a water em ission factor, however, in Indian construction a bore well was used to gather mixing water but it was not clear if the well was manually dug or dug with diesel equipment. In this study the emissions for are w hich is mainly because aggregate crushing in India more manually labor intensive.

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86 Table 3. 30 Summary of Emission Factors Leading Up t o Concrete Mixing. Table 3. 31 (2007) Emission Factor Calculations f or Ready Mixed Concrete

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87 3.8 MFA LCA of Cement Use in Rajkot A regional material flow analysis is meant for tracking the flow of materials that arrive at a specific region and are used in that region. The equation below shows the calculation for an MFA LCA. Where, EF LCI = emission factor from a certain material A report by Chavez, Ramaswami, Dwarakanath, Guru & Kumar. (2012) was one of the first MFA LCA for a city in a developing country that determined an MFA LCA for cement use in Delhi. The cement emission factor (EF) did differ from that calculated for 2 /tonne cemen t but was based on 1994 data from Hendricks et al (2004). The material flow analysis however was gathered year for all states and the city of Delhi. However, cement use in Rajkot was gether from a personal communication with an Ambuja representative (2011). An estimated 45,000 tonnes per month are designated for the city of Rajkot. The cement is dispursed for trade (small businesses) and non trade (large construction) u se. Therefore approximately 540,000 tonnes of cement are used per year. This information is shown in Table 3. 32 Using the EF calculated for cement, emissions from cement use in Rajkot per year is about 453,600 tonnes/yr.

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88 Table 3. 32 Information Regarding Rajkot Cement Use a nd Total Emissions p er Year Trade Non trade 20,000 tonnes/month 25,000 tonnes/month 540000 tonnes cement /yr MFA LCA = 453600 tonnes CO 2 /yr In Chapter 2 the total population was reported to be about 1.4 million. Therefore, percapita cement use is about 0.39 tonnes of cement/person. Chavez et al. (2012) cal culated about 0.50. 3. 9 MFA LCA for Concrete Mixtures in Rajkot Since exact material flows of aggregate are unknown for Rajkot it might be better to determine how much emissions a cubic meter of certain concrete mixtures used in Rajkot would result from using these mixtures. The calculation of an MFA LCa for a concrete mixture can be determined as follows: An MFA LCA was determined for a conventional M35 concrete pavement mixture and compared to pervious and H VFA concrete mixture. Table 3.3 3 shows the MFA data while Table 3.3 4 shows the LCA data. Table 3.3 5 shows the key material cement and how it changes for each mixture as well as final MFA LCA values. Pervious concrete provides a 21% reduction in emission s per cubic meter, while HVFA concrete provides about 47% reduction in emissions per cubic meter when compared to a traditional concrete pavement mixture.

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Table 3.3 3 MFA Data for M35 Pervious and HVFA Concre te Mixtures Table 3.3 4 LCA Data a nd Total Emissions Calculations f rom a n MFA LCA o n Concrete Mixtures 89

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90 Table 3.3 5 Cement Material Content a nd MFA LCA Emissions f or Certain Concrete Mixtures Key Material and Overall Emissions Traditional Pervious HVFA (50%) Cement (kg/m3) 400 312 196 Concrete Mixture MFA LCA (tonne CO2/m 3 ) 0.38 0.30 0.20 3.10 Summary The CMA reports a cement emission factor (0.83 tonnes CO 2 /tonne cement) very close to the calculations performed in this disseration for the state of Gujarat (0.84 tonnes CO 2 /tonne cement). However, it was necessary to perform the cement life cycle inventory because there are other contradicting sourc es reporting a range of emission factors for Indian cement (0.6 to 1.0 tonnes CO 2 /tonne cement). Actually this range is represenative of the how large companies and small companies have generate a majority of the electricity on site. However, many of the efficiency of production for the smaller companies are less than that of the larger companies which seems to make the emission factors fluctuate. Other materials and transportation needed for concrete revealed that much of the emissions is arising from c ement manufacturing. An MFA LCA of cement in Rajkot revealed per capita cement use in Rajkot is 0.15 tonnes/person more than Delhi but is still 0.11 tonnes/person below that of a U.S. city like Denver. Final MFA LCA calculations for pervious concrete and HVFA concrete mixtures showed at most a 21% and 47% reduction in emissions, respectively, compared to a conventional concrete used in Rajkot.

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91 4. Stormwater Solution Demonstration with Pervious Concrete: Structural and Environmental Tests In order to complete a pervious concrete system demonstration in Rajkot, India it was necessary to decide on an acceptable mixture and system design. Chapter 4 introduces the initial laboratory testing that was performed before commencing the study in Raj kot, India. Phase I of laboratory testing was based on mixture proportioning of 13.8 MPa (2000 psi) through Phase I testing, the mixture design was applied in Rajkot, India. The testing and results gathered from the pervious concrete project implemented in Rajkot is discussed in Chapter 4. Throughout the discussion on Rajkot it is explained that plans changed while on site and the pervious concrete field implementatio n changed into a small demonstration project. A perspective on international collaboration is also given in Chapter 4. The results gathered in Rajkot led to Phase II laboratory testing. The reality of having compulsory changes during the project such as curing techniques, and having different aggregate shape, and the shape of the test specimen are just a few reasons why a second phase of lab testing was needed in this study. The second phase of the study demonstrated that the effectiveness of a concrete technology (such as pervious concrete) serving as a climate adaptation solution is dependent on mechanical measured properties (i.e. compressive strength). The results of mechanical properties can also affect the decision of whether to use the technology in cities despite the technology satisfying other expected benefits (i.e. porosity, filtration).

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92 4.1 Study Design and Laboratory Phase I Testing As stated in Chapter 1 and 2 Rajkot Municipal Corporation and ICLEI South Asia were interested in adopting material interventions that would lead to helping the city develop urban infrastructure design for carbon mitigation and climate adaptation as well as help ing the city meet some of its lacking infrastructure needs. It was identified from ment plan (as discussed in Chapter 2) that the city needed improvements in stormwater management There was either very little to no stormwater infrastructure existing in the city. Initially a field demonstration of a pervious concrete system in Rajkot, India was agreed upon. A visit to Rajkot, India was made in January 2011 such that representatives from the University of Colorado Denver (Dr. Stephan Durham), ICLEI South Asia (Ms. Laasya Bhagavatula), Rajkot Municipal Corporation (Ms. Alpana Mitra and Mr. Mitesh Joshi) and Lakhlani Associates (Mr. Jayant Lakhlani) met and discussed the various projects to be researched in Rajkot. During this initial visit the site for the pervious concrete system was chosen. Figure 4.1 shows the initial site chosen fo r the pervious concrete system test section in Rajkot. The site was located at the Raiya wastewater treatment facility where they were placing a high volume fly ash (HVFA) concrete road. The size of the site was to be 3.5 m x 15 m (11.5 ft x 49 ft). The slope, location of drainage, and the availability of materials and equipment on site were reasons for choosing this area for the pervious concrete placement.

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93 Figure 4.1 Proposed P ervious Concrete System S ite Chapter 1 of this dissertation mentioned that the existing literature on pervious concrete did not discuss the transfer of pervious concrete mixture and system designs, that had been researched in the United States, to countries where not only materia ls (aggregate, water, and cement) differed, but construction techniques as well. Rajkot presented an opportunity to test a pervious concrete system. The same system and mixture proportioning that had been successfully used in a field demonstration in Den ver, Colorado as a parking lot pavement on the Auraria Campus (Hager, 2009) would be the model for the pervious concrete system pavement section to be placed in Rajkot. Figure 4.2 shows the parking lot pervious concrete system pavement placed on the Aur aria concrete pavement system. The pervious concrete pavement is blatantly called a system because there are two other important layers below the pervious concrete pavem ent. The layers usually are coarse aggregate directly below the pervious concrete and then fine aggregate. If the drainage design consists of a perforated pipe then another layer of c oarse aggregate is used to fill the trench where the perforated pipe s its (Refer to Figure Site for pervious concrete system

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94 4.3). The study by Hager (2009) used alternative materials (i.e. waste products) to replace the coarse aggregate and fine aggregate. As seen in Figure 4.3 coarse aggregate was replaced with recycled concrete and the fine aggregate wa s a mixture of sand and crushed glass. Above and below the crushed glass/sand was a geotextile fiber that prevented the sand from entering into the other layers. The system design for Rajkot y but the alternative design presented by Hager is a good model demonstrating the recycling of waste products aggregate content with at most 7.5% of total weight of aggregate a cementitious materials content between 311 kg/m 3 (525 lb/yd 3 ) and 326 kg/m 3 (550lb/yd 3 ) maximum 20% Class F fly ash, and a water/cementitious ratio of 0.3 0 improved the pervious imately 10% porous structure, and helped meet a design strength of 13.8 MPa (2000 psi) (Hager, 2009). Figure 4.2 Pervious Parking Lot P avement on Auraria Campus in Denver, Colorado Pervious Concrete Asphalt

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95 Figure 4. 3 D etails of the Pervious C oncrete S ystem for the P arking Lot I nstallation (Hager, 2009) 4.1.1 Material P roperties A Type I/II ordinary portland cement from Holcim, Inc. was used for Phase I laboratory testing. The specific gravity of the cement was 3.15. Chemical and physical p roperties of the cement are shown in Table 4.1 and 4.2 The maximum size of coarse aggregate used in the mixture design in the study by Hager was 9.5 mm (3/8 in). However, the availability of aggregate size was unknown for Rajkot. As such the size of agg regate used in this study was based on well graded aggregate that ranged from a maximum aggregate size of 25.4 mm (1.0) in to a nominal maximum aggregate size of 19 mm (0.75 in). Aggregates were provided by Bestway Aggregate in Colorado. The coarse and f ine aggregate both met American Society for Testing and Materials (ASTM) C33. The coarse aggregate met ASTM size number 57 and 67 gradation. A sieve analysis was performed by WesTest in Denver, CO for both the coarse and fine aggregate. The results of t he analysis are presented in the Appendix as Figure C.1 and Figure C.2. The specific gravity for the coarse aggregate was 2.61 with

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96 an absorption capacity of 0.6%. The specific gravity for the fine aggregate was 2.63 with an absorption capacity of 0.7%. Table 4.1 Chemical P roperties of Cement along with Standard L imits Table 4.2 Physical P roperties of C ement Along with S tandard L imits Although the fly ash decreased the compressive strength of the pervious concrete mixtures, it was assumed that long term strength would either be greater than or equal to

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97 th at of a 100% ordinary portland cement pervious concrete mixture (Hager, 2009). was made not to use fly ash in any of the mixtures designs. In fact, certain engineering officials in Rajkot were emailed, before the project was performed in Rajkot, regarding fly ash properties, but no information was provided. Thus, due to the possibility of decreasing compressive strength with the use of fly ash and the unknown propertie s of the sources of fly ash in Rajkot, no fly ash was used throughout the pervious concrete study. thaw resistance. However, in Rajkot freezing is not a concern. The temperature, as discussed in Chapter 2, in Rajkot is usually hot. In addition, a hydration stabilizing admixture was usually forms when all the paste and aggregate settle to the bottom of the placement of the pervious concrete. However, it was very likely that this type of admixture was not readily available in the city of Rajkot. No admixtures were used in the pervious concrete study. 4.1.2 Mixture D esign Table 4.3 lists the mixture designs for Phase I. Although 10% or more porosity was estimated by Hager from the voids present in the concrete mixture, there was no correction made to the assumed air content for the mixture design. Thus Mixture 1 of Phase I testing assumed a n air content of 2% as Hager did in 2009. However, a decision was made to assume an air content of 13% after testing for percent porosity of Mixture 1 (percent porosity is discussed in the results of the Phase I testing). Mixture 2 was

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98 assumed to have 13 % air content. Both mixture designs consisted of a cement content of 311 kg/m 3 (525 lb/cy 3 ), water cement (w/c) ratio of 0.3, and a fine aggregate content of 6% of total weight of aggregate. Table 4.3 Mixture Proportions for Phase I Laboratory T estin g 1 kg/m 3 = 1.6856 lb/yd 3 4.1.3 Test M ethods developing standards for testing permeability, compressive strength, flexural strength, fresh and hardened concrete density, void conte nt, and porosity. The ASTM Subcommittee C09.49 developed a standardized test for determining the density and void content of freshly mixed pervious concrete in 2008 referred to as ASTM C1688. ASTM C1688 was not used in this study; a couple of reasons bei ng that ASTM C1688 was fairly new and could be revised and it was the desire of the author to try an d mimic the preferred field compaction method of using a roller. ASTM C1688 requires the use of a standard proctor hammer to compact the pervious concrete. Standardized methods for compressive strength are still a work in progress by ASTM Subcommittee C09.49. As such, ACI committee 522 still refers to ASTM C39 for compressive strength testing of pervious concrete samples but ACI makes note that a better c ompressive strength test is needed. Standard procedures for preparing and curing pervious concrete samples and tests for porosity and hydraulic conductivity have yet to be established as well. The

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99 procedures for preparing and testing samples in this stud y are described in the next few paragraphs. Laboratory batching of pervious concrete is not discussed in ASTM nor ACI documents. Based on the procedures described by Hager (2009) and Tennis, Leming, & Akers (2004) the batching mostly followed the same p rocedures used for conventional concrete. However, mixing time was mostly dependent on the consistency of the mixture. The consistency of the mixture is best described in Tennis, Leming, & Akers (2004). The met hod of checking consistency helps determine if the water content is controlled. A handful of mixed pervious concrete is taken into the hand and shaped into a ball. If the mixture partially remains in the shape of a ball but leaves a lot of paste residue on the hands or void structure is hindered by too much paste then the mixture is (a) through 4.4 (c) is used to depict the three mixture consistencies. (a) (b) (c) Figure 4.4 Mixture C onsistency (a) T oo D ry, ( b) Proper Amount of Water, (c) T oo W et (Tennis, Leming, & Akers, 2004) Immediately after mixing was finished the pervious concrete was placed in the molds and the following procedure was used making specimens and curing specimens.

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100 Method of Preparing Specimens and Curing 1. Concrete was placed into 10.2 cm x 20.3 cm (4 in x 8 in) cylinders using 2 lifts. 2. Each lift was rodded 25 times 3. After rodding each layer the outsides of the mold were tapped with a mallet (or hand for plastic cylinder molds) 10 15 times. 4. The last lift was added such that approximately 3.2 mm (1/8 in) to 12.7mm (0.5 in) of concrete was above the rim of the mold just before compaction. The layer was then compacted with a rolling pin that weighed about 2.8 kg/m (1.9 lb/ft). While applying m y weight over the rolling pin, the actual weight being applied over the surface of the specimen was about 29.8 37.2 kg/m (20 25 lb/ft). The rolling pin was rolled over the surface until no more settlement was apparent. 5. The specimens were immediately covered with 6 mil (0.006 in, 0.15 mm) plastic. The plastic was sealed with tape. 6. The specimens were placed into a curing room that remained at a fixed temperature of 232 o C(733 o F) and humidity at about 55%. 7. The specimens were cured for 14 days befor e they were removed from the molds. While curing the concrete specimens were sprayed everyday for 14 days as part of the curing process. Spraying with water was done to mimic curing pervious concrete out in the field. Note: 15 cm (6 in) cubes and 25.4 cm x 25.4 cm x 17.8 cm (10 in x 10 in x 7 in) block samples were made in addition to the cylinders. The cube was placed using 3 lifts, rodding each lift 18 times, and the outside of the cube 10 15 times with a mallet after each lift was consolidated. The last lift was compacted with the rolling pin. Cubes were an essential testing element because in India cubes are the preferred shape to be tested for compressive strength. The procedure for the making the block was similar to the cylinders and cubes ex cept 4 lifts were used and each lift was rodded 50 times. Cores having 7.6 cm diameter x 17.8 cm lengths (3 in x 7 in) were drilled from the blocks. Hager hypothesized that compressive strength from cores best represented field strengths.

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101 The reason th e rolling pin was used for compaction was because in the field a roller usually weighing between 44.6 to 59.5 kg/m (30 to 40 lb/ft) or 0.44 kg/cm (2.5 lb/in) is used in the compaction. The rolling pin with weight applied was considered satisfactory for th ese samples especially if compressive strength was met. The method of determining compressive strength involved ASTM C39 with some modifications. The loading rate used for the cylinders was about 0.08 0.05 MPa/s (12 7 psi/s) and for the cubes the rate was approximately 0.04 0.05 MPa/s (6 7 psi/s). Lower loading rates, as compared to ASTM C39, were used because it was unclear whether the voids in the pervious concrete affect the ultimate strength at different loading rates; therefore it was ass umed a lower loading rate would provide a necessary caution. Additionally, ends of the specimens were sawed off if the testing surface of the samples needed to be level. At the most 1.3 cm (1/2 in) was sawed. The samples were then tested between two neo prene pads. The cubes, on the other hand, were tested between to steel plates. Figure 4.5 shows the difference between testing techniques for the cylinders and cubes. (a) (b) Figure 4.5 Co mpressive Strength Testing (a) U sing N eoprene P ads for C ylinders and (b) Steel Plates for C ubes Determining the percentage porosity of the pervious concrete is important towards the estimation of storage capacity (portion of the concrete that can be filled with rain).

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102 Tennis, Lemings, and Akers (2004) gave the example if the concrete has 15% porosity then a 25.4 mm (1 in) thick pervious concrete pavement could store 3.8 mm (0.15 in) of rain before the rain would no longer be stored and become runoff. Typical porosity can range between 15% and 25% (Tennis, L emings, and Akers, 2004). The following method was used to determine percent porosity: Method of determining percent porosity 1. Dry concrete sample 2. Weigh the dry concrete sample and record the value (W sdry ) 3. Weigh an empty container and record the value (W c ) 4. Fill the empty container with water to a certain level and call this the initial level (i.e. 20 cm from the bottom of the container) 5. Weigh the filled container and record the value (W c+w ) 6. Determine the mass of water in the container (W c+w W c = W w1 ) 7. Place the dry sample in the filled container (approx. 5 min) 8. Empty the water from the filled container until the water level is at the initial level 9. Weigh the filled container with sample and record the value (W c+w+s ) 10. Determine the mass of the water in th e container with the sample (W c+w+s W c W sdry = W w2 ) 11. w1 W w2 = W w3 ) 12. Convert mass of the water displaced to volume of the water displaced by dividing by the density of water (V w ) 13. Determine the volume of a solid sample based on sample dimensions (V ss ) 14. Determine the percentage voids [(V ss V w )/V ss x 100= P v ] 15. Cross check the calculation of percentage voids by determining the mass of water emptied from the container in step 8. (W w4 ) This also repres ents the mass of water displaced by the solids from the sample

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103 16. Convert the mass of water from step 15 into volume of water displaced by dividing by the density of water (V w2 ) 17. Determine the percentage voids [(V ss V w2 )/V ss x 100= P v2 ]. Hydraulic conductivity (also known as permeability and infiltration rate) is the flow rate through the concrete. According to Tennis, Leming, and Akers (2004) typical flow rates are 0.2 cm/s (288 in/hr) or higher. Hydraulic conductivity is important when designing the perviou s concrete system for stormwater management. However, the permeability of the pervious concrete is not the controlling factor; it is also necessary to know the permeability of the subgrade soils that the pervious concrete system will be placed on (Tennis, Leming, and Akers, 2004). In this study, however, only the method of determining hydraulic conductivity of the pervious concrete system was discussed. The procedure used for determining hydraulic conductivity is somewhat based on the falling head method The test was adapted from Delatte, Miller, and and Mrkajic (2007). The test is described as follows: Method of determining Hydraulic Conductivity 1. Use a 10.2 cm x 20.3 cm (4 in x 8 in) cylinder mold that has a 1.9 cm (3/4 in) hole drilled through the bo is secured to the bottom of the cylinder so as not to allow water to flow away from the cylinder when the cylinder is filled with water (See Figure 4.6) 2. Saturate the sample (i.e. make sure samples have been moistened completely) 3. Plug the hole of the cylinder with a stopper (make sure a rod or chain is attached to the stopper in order to pull it out without much disturbance to the water in the cylinder). 4. Place the testing apparatus (cylinde cylinder and surface of the sample. 5. Fill the cylinder with water until a near spherical shape of water forms at the top of the cylinder.

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104 6. Pull the stopper out of the cylinder while initiating a stop watch which i s used to record the time it takes for the water to drain from the cylinder. 7. Stop the stop watch once no water is seen draining from the 1.9 cm (3/4 in) hole. 8. To calculate the water the following equation is used Where, k = hydrauli c conductivity (length/time) a = cross sectional area of cylinder (not 1.9 cm (3/4 in) hole)(length 2 ) A = cross sectional area of sample (length 2 ) L = length of sample (length) t = total time to for water to drain from cylinder (time) h 1 = initial water level (length) h 2 = final water level (length) ln = natural logarithm 9. Although the cylinder is allowed to drain completely, h 2 is not exactly zero. Some level of water is left near the bottom of the cylinder and can be measured by pouring into a graduated cylinder. The volume of water in the graduated cylinder is divided by the area of the cylinder to get an approximate height of the wate r which is h 2. (a) (b) Figure 4.6 Hydraulic T esting A pparatus (a) C ylinder with Stopper and Putty (b) Hole Drilled in Cylinder for Draining W ater from the Cylinder into the Pervious C oncrete 1.9 cm (3/4 in) hole Putty Cylinder Stopper w/rod

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105 4.1.4 Phase I laboratory results Density The fresh concrete density was determined very similarly to the pro cedure described in ASTM C138, however, the last layer of pervious concrete was compacted using the rolling pin. Density for Mixture 1 was accidently not recorded. The density for Mixture 2 was recorded as 1922 kg/m 3 (120 lb/ft 3 ). According to Tennis, L eming, and Akers (2004) typical unit weights range between 1600 kg/m 3 and 200 kg/m 3 (100 lb/ft 3 and 125 lb/ft 3 ). Mixture 2 falls within these typical unit weights. Unit weights are considered to be a proof of whether mixture proportions are consistent (i .e. quality control) especially when it comes to jobsite mixture deliveries. Porosity Both mixtures were tested at 7 days of curing. The samples were supposed to be tested at 28 days of curing, however, the project in Rajkot had to be scheduled during t he curing days of Mixture 1 and Mixture 2 so Mixture 1 was cured up to 23 days and Mixture 2 was cured up to 15 days. Table 4.4 shows the percent porosity recorded for the samples. Table 4.4 Porosity of S amples from Mixture 1 and Mixture 2 (Reported in Percent) Mixture 1 cured up to 23 days ** Mixture 2 cured up to 15 days

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106 Tabl e 4.4 does show differences in percent porosity between curing days. However, the percent porosity was not expected to change by muc h between curing days. By at least 7 days the cement paste should have hardened and movement perhaps should have been limited to micro movements. Changes in % porosity between curing days would most likely be due to random orientation of aggregate especi ally if non uniform graded aggregate is used. In addition, Table 4.4 shows how the cored cylinders for both Mixture 1 and Mixture 2 resulted in a higher percent porosity compared to the other cylinders and cubes. This could be an example of how a sample with greater area may not get rodded as well as a smaller sample. Although there were some differences in % porosity among the different samples the recorded values fall within the typical range of 15% to 25% according to Tennis, Leming, and Akers (2004). A side by side compa rison of the samples is shown in Figure 4.7. From Figure 4.7 the voids within the samples are visible. Figure 4.7 A Side by Side Comparison of the Pervious Concrete S amples Hydraulic Conductivity In Phase I lab testing the hydr aulic conductivity was determined only using the large pervious concrete blocks before coring them (as seen in Figure 4.6). Using the

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107 recorded for Mixture 1 and 2 are lis ted in Table 4.5. A value was accidently not recorded for Mixture 1 at 7 days of curing. Table 4.5 represents the average of at least three tests performed on the samples. The test results, overall, yielded a range of hydraulic conductivities from 0.22 c m/s (0.09 in/s) to 0.41 cm/s (0.2 in/s), which is higher than the lowest typical flow rate of 0.2 cm/s (0.08 in/s) as reported by Tennis, Leming, and Akers (2004). Originally Delatte, Mrkajic, and Miller (2009) called this method of determining hydraulic conductivity the drain time test. Delatte, Mrkajic, and Miller (2009) performed drain time tests in several locations where pervious concrete was placed as parking lots and sidewalks. Cores were taken from these locations and falling head tests were perf correlation between drain time test and hydraulic conductivity. Because the various sites they visited were based on different mixture designs and most likely aggregate gradatio n the authors suggested that the correlation between drain time test and falling head test be rationalized through the following empirical formula. Where, k = hydraulic conductivity from laboratory tests (in/hr) t = drain time test (s) If the average drain time values ranged from 27 s to 44 s for Mixture 1 and 2 then by Delatte, Mrkajic 0.34 cm/s (475 in/hr) to 0.12 cm/s (166 in/hr). This range is close to the values reported in Table 4.5, therefore, either relating the test method values directly to the falling head test or the empirical formula is appropriate.

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108 Table 4.5 Average Hydraulic C onductivity for Mixture 1 and 2 Mixture 1 cured up to 23 days ** Mixture 2 cured up to 15 days 1 cm/s = 0.3937 in/s Compressive Strength All recorded values for compr essive strength are shown in Table 4.6a and Table 4.6b and the average compressive strengths are displayed in the Figure 4.8. The design strength was 13.8 MPa (2000 psi). By 7 days of curing both Mixture 1 and 2 demonstrated that cylinders and cubes wer e nearing design strength. For this study it was desired to have the 10.1 cm x 20.3 cm (4 in x 8 in) cylinder as the reference for strength, meaning that the strengths of cubes and cores could be related with a strength ratio or factor. According to Mind ess, Young, and Darwin (2003) the common cube to cylinder strength ratio is 1.25. This factor means that the cube strength is usually higher than the cylinders. However, upon comparing cylinders and cube compressive strengths for both Mixture 1 and Mixtu re 2, the cube compressive strengths were lower than the cylinder strength. At this point in the study, a strength conversion factor used to attain an equivalent cylinder compressive strength for cubes was not determined. For the 7.6 cm x 17.8 cm (3 in x 7 in) cores the length to diameter ratio is 2.3. ASTM C39 only lists strength conversion factors for length to diameter ratios equal to or less than 1.75. But, Mindess, Young, and Darwin (2003) did provide a compressive strength factor equal to about 1.03 which represented the cylinder to core ratio. This meant the resulting core compressive strengths are usually lower than the cylinders.

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109 By the 23 rd and 15 th day of curing, the cores had increased in strength and if multiplied by the 1.03 factor the ave rage values would be about an equivalent cylinder value equal to 12.3 MPa (1784 psi) and 13.3 MPa (1929 psi) for Mixture 1 and Mixture 2, respectively. However, cubes compressive strengths did not increase. Figure 4.8 shows two trends for the cubes. Com pressive strength results, for Mixture 1 cubes, decreased by as much as 7 MPa (1015 psi). While Mixture 2 cubes had mostly remained consistent with 7 day compressive strengths, both mixtures never reached 13.8 MPa (2000 psi) according to cube compressive strength results. The cylinders, however, did reach and pass the design strength by 15 days of curing. The relationship between the cylinders and cubes was still in question but the success of the cylinders passing design strength by as much as 2.2 MPa ( 319 psi) was satisfactory for producing pervious concrete in Rajkot, India. Besides, a trial mixture would be completed in Rajkot, India before proceeding with the field placement. Table 4.6a Mixutre 1 Compressive Strength R esults 1 MPa = 145.038 psi

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110 Table 4.6b Mixture 2 C ompressive Strength R esults 1 MPa = 145.038 psi Figure 4.8 Average Compressive S trengths for Mixture 1 and Mixture 2 Some observations made during the compressive strengths tests revealed that the cylinders and cubes fractured in certain patterns. For example, Figures 4.9a and 4.9 b show at least two paths the fracturing took during compressive strength testing of the c ylinders. The fracture paths that most commonly occurred for the cubes during the test are shown in Figure 4.10. In the figures, a generalized vertical line is used to represent some of the fracture paths but the actual paths followed the location of the voids and paste surrounding the aggregates. There were examples where the fracture occurred 1 MPa =145.038 psi

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111 through the aggregate as seen in Figure 4.11. If the fracture occurred through the aggregate this is could be a good indication of the bond between the paste and aggregate. (a) (b) Figure 4.9 Fracture Paths for Cylinder Pervious Concrete S amples Figure 4.10 Fractur e Paths for Cube Pervious C oncrete S amples Figure 4.11 Fracture O ccurring Through the Aggreg ate

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112 4.2 Providing Stormwater Management Solutions in Rajkot, India: A Pervious Concrete System Demonstration. As published in The International Journal of the Constructed Environment (Solis, Durham, Ramaswami, 2012) 4.2 1 Introduction drainage in the city was evaluated. The assessment revealed that Rajkot is still dependent on reservoirs and natural courses (nalas) that exist around the city to redirect storm water to the Aji River which is on the west side of the city. However, present natural courses are polluted and frequently used as waste streams. Additionally, many of the natural courses have been covered by reinforced concrete slabs due to urban developm ent. Natural basaltic roads, hard rock, and mineral soils also make it difficult for stormwater to seep into the ground, therefore, allowing water to accumulate on the surface with just rainfall intensities of 100 mm (4 in.). (Rajkot Municipal Corporation, 2006). Within the development plan, the city expressed concerns that the flooding would cause health hazards from accumulation of stagnant water and solid waste around the city. Also, there had already been road and property damage identified due to lack of proper stormwater drainage. Solutions for stormwater management in Rajkot include cleaning existing natural courses and installing stormwater pipelines and gutters that link to the natural courses. In addition to these solutions, the unique pavement t echnology known as pervious concrete can help Rajkot meet stormwater drainage demands while meeting certain growing environmental demands. Pervious concrete has been recognized by the EPA as a Best Management Practice (BMP) for reducing stormwater runoff, recharging groundwater,

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113 and reducing pollutant concentrations (Tennis et al., 2004). BMPs are mitigation solutions to the adverse impacts of urban development. Pervious concrete has benefits that fall into three categories: environmental, economical, and s tructural. It is considered environmentally beneficial because it has the ability to capture stormwater, filter the water as it captures it, and depending on the system design, it can replenish the groundwater directly, or captured water can be directed to wards a city drainage system. Capturing of stormwater can also reduce runoff. In comparison to asphalt pavements, pervious concrete will absorb less heat. If used around landscaping, pervious concrete can possibly provide water and more air to the trees (N RMCA, 2004). The economical benefits might include reducing the number of retentions ponds and reducing the need for the large capacity of storm sewers. Structural benefits are due to the texture and strength of the concrete. A textured surface due to coar se aggregate exposure provides traction for drivers. Strengths of pervious concrete can range between 2.76 to 27.5 MPA (400 to 4000 psi) (Kosmatka, et al., 2002). Plan Modifications As stated previously the field installation was going to occur at a wast e water treatment facility. The location of the field installation changed because the project was dependent on construction occurring on site. In other words, Rajkot Municipal Corporation and Lakhlani Associates preferred to use materials for the pervio us concrete from other projects being constructed nearby. The new location was on location where an elevated water tank was being constructed. Figure 4.12 shows the second proposed site for the pervious concrete. An AutoCAD drawing of the proposed pervi ous concrete system profile was prepared for the site and is presented in Figure C3 in the Appendix.

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114 Figure 4.12 Second Proposed Site for the Pervious Concrete System P lacement Discu ssion on the second proposed site resulted in a few concerns: Uncertainty in the quality of materials The second site was proposed due to variability in compressive strength attained from the concrete project occurring at the original site. Although it was suggested that changes in weather may have caused variable material properties for the concrete at the waste water treatment site there was concern that similar problems would occur at the second proposed site. It is very important that pervious concr ete reach adequate strength Uncertainty in the grading of the land for drainage The second site appeared very flat or there was not proper grading for drainage to flow over the pervious concrete. Pervious concrete will only work if there is adequate drainage and a holding place for the water. Uncertainty whether there was enough time allotted for construction of the pervious concrete system It was not clear whether workers on site would leave for a festival during the month of construction of the p ervious concrete Possible area designated for the pervious concrete system

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115 Uncertainty of whether the pervious concrete system would be replaced within a few months for placement of an asphalt pavement The original design of the elevated water tank site included an asphalt pavement road to be installed before t he monsoon period. It was not clear whether the contractor would allow a long term installment of the pervious concrete system. Long term data was necessary for the field demonstration of the pervious concrete system in order to gather accurate conclusio ns about the system subjected to field conditions especially during the monsoon period. Overall, there was the concern that all parties involved would be investing time, labor, materials, and cost with some of these uncertainties and concerns not fully b eing resolved. The representatives of the University of Colorado Denver did not want a negative experience to result based on these uncertainties and prevent a new technology from being adopted. An alternative was presented to Rajkot Municipal Corporatio n and ICLEI South Asia such that a smaller demonstration project would be completed to show the following benefits of the pervious concrete system : Reassurance of the quality of material for pervious concrete, Assurance of adequate strength gain for the pe rvious concrete, Demonstration of drainage capabilities and hydraulic conductivity Comparison of water quality before and after percolation of simulated stormwater through the pervious concrete system The smaller demonstration project involved the construction of a small above ground pervious concrete system in a large (approx. 208 L [55 gal]) trash can, barrel, or container. The container was filled with three layers of material (150mm (6 in) of sand,

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116 150mm (6 in) of good draining rock, and 150mm (6 in) of pervious concrete). An outlet pipe was constructed at the base to allow water to flow out of the demonstration pervious concrete system. All parties agreed to the alternative demonstration and the small demonstration project was completed at the water tank site where materials and equipment were available for use. Based on compressive strength results of pervious concrete samples and the potential to improve water quality of storm water Rajkot Muni cipal Corporation and ICLEI South Asia may consider a field installation of the pervious concrete system at a later date. In this dissertation, the results of a small pervious concrete pavement (PCP) demonstration executed in Rajkot are presented. The main objective of the demonstration was to determine the potential of using a pervious concrete system for stormwater management in Rajkot. The test results provided insight into whether the materials available in Rajkot were suitable to ta ke advantage of the three main benefits of pervious concrete (environmental, economical, and structural). 4.2. 2 Materials and Methods Preparation of Base and Sub base A comprehensive design of a PCP includes the drainage, base material, and finally the pe rvious concrete. These three design criteria provide a stormwater management system with the capabilities of capturing stormwater, filtering the water, and providing durability and resistance to loadings. Preparation of the PCP system demonstration require d the use of a barrel, with the dimensions 0.62 m (Length) x 0.4572

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117 m (Diameter) (L 24.5in x D 18 in). A hole was made about 38.1 mm (1.5 in) from the bottom of each barrel so that a perforated PVC pipe with an outside diameter of about 32 mm (1.5 in) co uld be placed in the barrel and through the hole. The perforated pipe had the purpose of collecting and draining the water that percolated through the system. Figures 4.13a and b illustrate how the perforated pipes were placed in the barrels. One end of th e perforated pipe was sealed off with electrical tape to allow water to exit only one end of the pipe. The pipes were also provided with about an 8% slope to force water to exit through the open end of the perforated pipe. The slope was provided by placing a 76.2 mm (3 in) brick underneath the taped end of the perforated pipe. Layers of 20 mm (~ in) coarse aggregate and fine aggregate were placed in the barrels (Refer to Figures 4.14a and b). A cloth fiber was used in place of a geotextile fiber between t he coarse aggregate and sand layers (Refer to Figure 4.15). The cloth fiber was more readily available than the geotextile fiber. The fabric had the purpose of allowing water to percolate through the various layers but preventing the fine aggregate from cl ogging the layers of coarse aggregate and pervious concrete. Figure 4.16 shows the schematic of how thick the layers of aggregate were and their locations in the barrel. After all layers had been placed in the barrel, the layers were compacted with a bloc k of wood that was available on site. The layers were allowed to settle for two days and then were provided additional compaction by pouring at least two 8 L (2 gal) buckets of water into the barrels just before placement of the concrete layer.

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118 (a) (b ) Figure 4.1 3 ( a) A P erforated P ipe P laced in B arrel ( b) I mage of B arrel (a) (b) Figure 4.1 4 Base and Sub B ase Layers a) Coarse Aggregate Layer b) Fine Aggregate Layer Figure 4.1 5 Cloth Fiber used b etween Coarse and Fine Aggregate Layers

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119 Figure 4.16 Profile of the Pervious Concrete System Placed in the Barrel Batching and Curing the Pervious Concrete System The pervious concrete for the small demonstration was batched during an ambient temperature between 29.4 o C (85 o F) and 32.2 o C (90 o F), which fell below or equaled to the maximum recommended batching temperature of 32.2 o C (90 o F) (CRMCA, 2009.). The mixture design was based on 311 kg of grade 53 ordinary portland cement per cubic meter of concrete (which is equivalent to a Type II cement a t about 525 lb/yd 3 ). The design water to cement ratio (w/cm) was 0.30. No admixtures were included in the design. The design air content was 13%. The expected air content was based on an average of measured percentage voids that resulted from pervious concrete mixture experiments performed in lab. 6% fine aggregate of total aggregate was also included in the mixture design. The mixture design is shown in Table 4.7 and batch quantities are presented in Table 4.8 and the mixture.

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120 Table 4.7 Mixture P roportions for Rajkot 1 kg/m 3 = 1.685 lb/yd 3 Table 4. 8 Batch Quantities Material Quantity Grade 53 Cement 26.1 kg (57.5 lb) Water/cement ratio 0.3 Coarse aggregate 20 mm (0.8 in) 83.4 kg (183.9 lb) Coarse aggregate 10 mm 12 mm (0.4 in to 0.47in ) 59.2 kg (130.5 lb) Fine Aggregate 9.2 kg (20.2 lb) Water 9.4 L (2.38 gal) The specific gravity of the cement and aggregate was provided from a representative of Ambuja Cements Ltd. The values of specific gravity are given in Table 4.9. Unfortunately, no one could provide the absorption capacity for the aggregates. It was assumed that the absorption capacity would be 1.00 just for simplicity. Additionally, the moistur e content of the aggregate is either not determined or not frequently determined for on site construction. Therefore, the moisture content was assumed to be zero if the aggregate was exposed to the sun and dry weather conditions. Table 4.9 Specific Grav ity Values P rovided used in the Pervious Concrete Mixture D esign During the process of mixing the batch, the consistency was checked about three times. Only about 7.1 L (1.9 gal) of water had been added before the initial assessment of the batch. At tha t time, the mix was too wet. Approximately 0.4 kg (0.9 lb) of cement and 1 L (0.3 gal) of water was added to the mixer. A second assessment of the consistency was

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121 made, once again the mix appeared to be too wet. Another 0.4 kg (0.9 lb) of cement and 0.7 L (0.2 gal) of water was added to the mix. The additional cement and the amount of water finally added changed the water/cement ratio from 0.3 to about 0.33. Using Tennis, pervious concrete was shaped into a ball, and some aggregate stayed intact with each other (See Figure 4.17). Figure 4.17 Evaluation of Pervious Concrete Consistency As stated previously, the base and sub base materials in the barrel were compacted by saturating the material with two 8 L (2.1 gal) of water before placing a 0.15 m (6 in) layer of pervious concrete as the final layer in the barrel. Six 15 cm (6 in) cubes (See Figure 4.18) were made such that three cubes were reserved for 7 day and 28 day compressive strength tests. The cubes were made following Indian Standards IS 516 (2002). Dur ing Phase I laboratory testing cubes were made following the steps shown under section 4.1.2 During Phase I testing Indian were not available. However, the only difference between steps previously discussed in 4.1.2 compared to the Indian Standards was the number of

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122 roddings used for each lift. Therefore each layer or lift was rodded 35 times versus 25 times. Additional modifications were made when compacting and curing the cubes. For example, a wood block (See Figures 4.19a and 4.19b) or steel mold was the tool used in the compaction process for the cubes and barrel respectively because a roller or mallet was not readily available. 6 mil plastic was also not available, so curing proceeded with the use of polypropylene cement bags and wet jute bags. A fter about 3 or 4 hours of initiating the pervious concrete cubes and small demonstration barrel all concrete was covered with a wet jute bag (See Figure 4.20). Figure 4.18 R odding the Layers of Pervious Concrete in the Cube M old (a) (b) Figure 4.19 C ompacting the Pervious Concrete in the Cube Molds Using (a) Direction 1 and (b) D irection 2

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123 Figure 4.20 C overing the Pervious Concrete with a Wet J ute B ag Removal of Pervious Concrete from Molds The pervious concrete cubes were removed from the mol ds after curing for 24 hours. In Phase I lab testing the cubes were cured such that the samples remained in the molds and covered in 6 mil plastic for 14 days. Each day the samples were sprayed with water. Since the pervious concrete demonstration was o ccurring on location where the water tank was being constructed, the molds were needed for the sampling during the water tank construction. While removing the cubes from the molds, the cubes remained well intact, demonstrating good cohesiveness (See Figur es 4.21a and 4.21b). As indicated by IS 516 and ASTM C39, the cubes were placed in a water bath for curing. The concrete cubes were placed in empty cement bags and then placed in the water bath which was on site (See Figure 4.22). (a) (b) Figure 4.21 R emoval of Pervious Concrete from Cube M olds (a) Close Up V iew (b) A ll Six C ubes

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124 Figure 4.22 P lacing Pervious Concrete Cubes in a Water B ath 4.2. 3 Test Methods and Results Percentage Voids and Hydraulic Conductivity Test The percentage voids test was c ompleted when the cubes were tested for 7 day compressive strength. The procedure used in determining percentage voids was the same used in Phase I laboratory testing. Figure 4.23 provides a depiction of how each concrete cube was placed in separate conta iners to determine percentage voids. Figure 4.23 P lacement of the P ervious Concrete Samples in Water Filled C ontainer to Determine Percentage V oids fro m Volume of Displaced W ater The average of percentage voids fell within the suggested range (15% to 25%) by Tennis et. al (2004) as seen in Table 4.23. Voids are not uniform in size and are not distributed

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125 evenly within sample, thus, the duration for soaking the samples in water can affect the calculations for percentage voids. Table 4.10 R esults of the Calculated Percentage V oids Two tests were performed to determine a hydraulic conductivity value for the pervious concrete and the pervious concrete system separately. Hydraulic conductivity can be used to describe the movement of water through the media over time. The hydraulic cond uctivity test for the pervious concrete was performed using the method described in test. The hydraulic conductivity test for the entire pervious concrete system includ es the effect of the layers of aggregate, geotextile fiber, and pervious concrete on the system. Thus, the hydraulic conductivity test for the system was conducted such that the system within the barrel was filled with water until approximately 10.2 cm (4 in) of water covered the surface of the pervious concrete. The water was allowed to percolate through the system until 7.6 cm (3 in) had drained from the initial height of water. The test was performed twice and the drain time was used to calculate the hyd raulic conductivity. Table 4.11 shows average hydraulic conductivities for the pervious concrete and the system separately. Note: Table 4.11 was modified to better represent a falling head test and take into account the length and surface area of the perv ious concrete and the system. Therefore this table differs from that reported in the article by (Solis, Durham and Ramaswami, 2012)

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126 Table 4.11 H ydraulic Conductivity of the Pervious Concrete and S ystem According to Bear (1972), the hydraulic conductivity range for a pervious material is 0.1 to 10 2 cm/s. The pervious concrete had a hydraulic conductivity of about 0.33 cm/s (0.13 in/s) and thus fell within this range. The hydraulic conductivity for the pervious concrete may have been over estima ted. This is suggested because the drain time for the cylinder mold alone is about 9 seconds. While the drain time for the pervious concrete in Rajkot was measured to be an average of about 10 seconds. This may have been due to the seal between the hydr aulic conductivity apparatus (i.e. cylinder mold) and top surface of the concrete being loose. However, this measured hydraulic conductivity could be correct because the surface area of the sample is much larger compared to the samples tested in lab. The calculation for hydraulic conductivity incorporates the surface area of the sample as compared to the surface area of the cylinder mold. Using the empirical equation, established by Delatte, Mrkajic, and then the equivalent hydraulic conductivity is 9.7 mm/s (0.38 in/s). The empirical equation reports a hydraulic conductivity 6.3 mm/s (0.25 in/s) higher than the falling head equation. This difference might be explained by the characteristics of the sampl es tested by Delatte, Mrkajic, and Miller (2009). Aggregate gradation is not discussed in their study, however, it was mentioned that many of the samples were taken from pavements that were raveling and

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127 had some clogging. For this study, relating the dra in time test directly to the falling head equation is preferred. The pervious concrete system had a hydraulic conductivity of about 0.03 cm/s (0.01 in/s) and fell within a range of 10 1 to 10 2 cm/s, which is representative of well sorted sand or a mix o f sand and gravel. The pervious concrete system consists of the layers of coarse aggregate and sand along with the pervious concrete as the top layer. Thus, the controlling layer for the hydraulic conductivity of the system would be dependent on the sand, which is represented by the 0.3 mm/s in Table 4.11. Compressive Strength Testing of Pervious Concrete Cubes Three cubes were tested as recommended by IS 516 and ASTM C39 for compressive strength at 7 and 28 days of curing (See Figure 4.24). At 7 days, vis ual observations of the tested sample revealed that the cement paste was soft and was still in the process of curing. Figures 4.25a and 4.25b show the cement paste had not hardened completely (which was expected since maturity can vary based on design of t he concrete and must be determined by laboratory testing [CRMCA, 2009]) and broke into small sand like pieces rather than large stiff chunks. In fact, Phase I testing required that the samples remain covered with the 6 mil plastic for 14 days. However, t his type of curing was not an option for the samples in Rajkot, instead the samples, remained in the curing bath up to 7 and 28 days of compressive strength testing. The results of the three tests and the average of the three tests for each day are repor ted in Table 4.12. As stated previously, the compressive strength of pervious concrete can vary. Traditional concrete pavements can have compressive strengths between 20.7 MPa and 34.5 MPa (3000 psi and 5000 psi). It was expected to achieve at

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128 least a 13.8 MPa (2000 psi) by 28 days. By the 7 th day, the pervious concrete specimens had reached half the strength that was expected (Refer to Table 4.12). However, at 28 days of age, the sample strengths varied between 5.5 MPa and 13.2 MPa (795 psi and 1908 psi). Strength results fell within the possible range of applicable pervious concrete strengths but were about 4.6% below design strength, which suggests that this particular mix design could serve, better, as a pavement for lighter loads experienced by sidewalk s. Figure 4.24 C ompressive Strength T est and Fracture P ath (a) (b) Figure 4.25 V isual Observations (a) The S ample after Completion of Compressive S trengt h Test (b) Breaking the Sample F urther by H and

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129 Table 4.12 R esults of Compressive S trength of Pervious C oncrete S amples Water Quality Testing and Results Water from a bore well and water from a nala (stream) on the North West side of Rajkot city were used to test the potential of the pervious concrete system to filter the water. Water samples were submitted to the K.C.T. Consultancy Services in Ahmedabad for metals testing and to the Gujarat Pollution Control Board in Rajkot for pathogens and other property testing. Two sources of water were chosen for the purpose of examining the effe ct that the pervious concrete system had on the water quality of an assumed clean source of water (i.e. bore well) versus a source of water that could represent stormwater (i.e. stream). The water samples were placed in 5 L (1.3 gal) rinsed plastic contai ners (Figures 4.26a and 4.26b) and 300 ml sanitized glass bottles (Figures 4.27a and 4.27b). Observations of the water samples were made before and after percolation. Figure 4.26a shows the well water samples before (container A) and after (container B) p ercolation through the pervious concrete system. The color of the water may have changed after percolation through the system as seen with container B. In Figure 4.26b container Y holds the stream water before percolation, and container X is the sample aft er percolation. The color of the stream water after percolation is significantly different and supports the idea that certain constituents of the water are being filtered. Figure 4.27a and

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130 4.27b also show the difference in color that occurred with the well and stream water after percolation. Figure 4.26 B efore and after P ercolation (a) Bore Water S amples (b) Stream Water S amples Figure 4.27 S amples Collected for Pathogen and B.O.D. T ests (a) B ore W ell Water Samples (b) Stream Water S amples Water quality test results for the two sources of water are shown in Table 4.13. The results are compared to available drinking water criteria from BIS IS 10500, Central Pollution Control Board in India, and U.S. Environmental Protection Agency (EPA). A co mparison is also made with the limits for freshwater criteria available through the U.S. EPA. Stormwater quality in the U.S. is often compared to freshwater (or individual cities or states have established criteria), thus, Table 4.13 uses both drinking and freshwater criteria comparisons since freshwater criteria for India could not be found at this time.

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131 Table 4.1 3 Water Quality Analysis of the Water from a Bore Well and Stream In Table 4.13, the cells that have been highlighted in red indicate that the results are above the standard limits. Also, some values increased after percolation through the pervious concrete system. For example, the pH increased in alkalinity for both the well and stream water samples. Concrete has a high pH due to the presence of calcium hydroxide, which forms from the reaction of Portland cement and water. The findings on pH levels are similar to studies performed by Hager (2009) and Caulkins, Kney, Sule iman, and Weidner (2010), where pH levels of water, after passing through their pervious concrete samples, resulted in pH values between 11 and 12. Although, more

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132 studies are needed to determine whether pH levels reach a neutral level after several flushes it has been suggested that high pH levels could act as good buffers to treat acidic water or acid rain (Hager, 2009 and Majersky, 2008). Table 4.13 shows turbidity, chloride, and sulphate levels increased after percolation but remained below standard li mits. Stream water had high values for limits. High levels of nitrogen, nitrate, and nitrite might be explained from the leaching of human and animal into the stream water If true, the leaching could be occurring during the flooding events. These high levels may also suggest the presence of pesticides and inorganic and organic compounds that can cause health problems. But the ammonical nitrogen levels decreased after filtr ation through the pervious concrete, thus, meeting out high levels of nitrogen. Total and fecal coliforms levels were high before and after percolation through the per vious concrete system. A specific value was not determined for the coliforms because it was possible that during testing for pathogens, using the Most Probable Number (MPN) method, not enough dilutions were made to make a more accurate estimate of pathogen s. Nevertheless, the presence of coliforms in concentrations of 200 MPN/100 ml can be associated with disease causing illnesses or organisms that are most likely present in the water. In India animals such as cows are allowed to roam the streets and any f ecal left from the animal could collect in runoff during the rain events. This dissertation supports the idea that pervious concrete can filter out some pathogens. Although the water quality testing in this dissertation did not support this idea (mainly due to a lab error) a study by Luck, Workman, Coyne, and Higgins (2008)

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133 simulated rainfall over pervious concrete that had been exposed to manure. The effluent passing through the pervious concrete was tested for dissolved organic carbon, ammonium, nitrat e, nitrite, total nitrogen soluble phosphorus, and fecal coliforms. Effluent was tested for three weeks. Within the first week one third of the original concentration of fecal coliform forming units (cfu) was detected. By week 2 and 3 fecal coliforms were below the detection limits (<2000 cfu/100ml) of the device used during testing (i.e. spiral plating device). Overall the study indicated that the total reduction in coliforms was 10,000 fold compared to the coliforms originally present in the manure The study suggested that the reduction in coliforms might be explained by (1) coliforms are trapped in the concrete since some effluent is initially absorbed by the concrete material and (2) fecal coliform can die off in alkaline environments. The pH o f the effluent can exceed 9 due to the concrete as is seen with this dissertation. The cells highlighted in yellow also show values that are slightly above some standards. These values are no higher than 50% of the highest standard limit such as zinc a nd aluminum. Certain metals such as iron, zinc, and aluminum can have a positive effect on human beings. However, exposure to these metals shall meet the minimum drinking water level requirements since total intake of such metals already come from other so urces. Too much exposure to metals can have short and long term health effects. Table 4.14 shows results for the majority of the metals that the stream water was tested for (before and after percolation). Although Rajkot is known for its manufacturing ind ustries (i.e. engines, cutlery, bearings, and casting) surprisingly no metals were detected in the samples before and after percolation. If an error occurred during sampling before metals testing it may have occurred when nitric acid (HNO 3 ) was directly a pplied

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134 to the water to be tested. Normally, the containers that will hold the sample are pre cleaned with nitric acid instead of the nitric acid being directly applied to the water sample. Additionally, the samples had to be transported for about 3 hours to Ahmedabad so the samples could have been affected by improper transportation. Note: Currently, Rajkot does not have criteria or standards for stormwater limits. Conclusions This study demonstrated that the aggregate and cement materials available i n Rajkot can be used for the construction of a pervious concrete system. The pervious concrete and the system revealed reasonable porosity, hydraulic conductivity, and filtering capabilities that can be beneficial with the management of stormwater. Table 4 .14 Additional Results of Stream Water Quality Tests Concerns with strength and filtering of pathogens and attaining consistent results in all tests have led to a few recommendations. Such recommendations include the following:

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135 Additional water quality t ests should be performed with the same stream water. The range of testing (or dilutions) for coliforms should be increased to guarantee specific values for before and after filtering of water sample tests. Another pervious concrete mix should be performed using the same mix design to check consistency in strength results. If strength results remain below 13 MPa (2000 psi), the mix design can be revised to include materials such as silica fume and fibers to increase strength and bond strength between the ag gregate and cement paste. It is also important to note that cube and cylinder strength tests can give varying results and should be compared with each other Current strength results reveal that pervious concrete can be used in pedestrian pathways or for landscaping where light loads are expected. Literature has shown that successful strength is dependent on proper compaction of pervious concrete. Quality assurance in compaction can be related to a unit weight test such that acceptable values for cylinders range between 1600 kg/m 3 and 2000 kg/m 3 (100 lb/ft 3 and 125 lb/ft 3 ) (Tennis et. al, 2004). This relation between unit weight, compaction, and strength should be investigated further if strength results continue to fluctuate. First impressions of the perv ious concrete mix and placement suggested that there is interest in using the pervious concrete. However, proper field implementation requires proper training of employees and appropriate understanding of tools needed during placement. Figures 4.28a and 4. 28b show the steel roller that might have been used for compaction if a large scale field demonstration of the PCP system had been performed. According to studies by Kevern et. al (2009), a steel

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136 roller should be of appropriate weight. Weights can range be tween 18 and 30 kg/m (12 and 20 lb/ft) depending on the workability of the pervious concrete. (a) (b) Figure 4. 28 S teel Roller for C ompaction (a) Side V iew (b) F ront V iew 4.3 Laboratory Phase II Testing ( Cubes Versus Cylinders ) Throughout this section the author makes reference to results and experiences with Phase I testing and Rajkot pervious concrete testing. The goal of the pervious concrete project in Rajkot was to demonstrate to the city that future stormwater infrastructu re projects could incorporate a type concrete technology that also provided environmental, economical, and structural benefits. Additionally the demonstration aim to prove that Rajkot materials, although different from materials used successfully in the U .S., would still contribute to a successful mixture design. In fact the mixture design was adequate for achieving common percentages for porosity, hydraulic conductivity fell within a range representing pervious material, and there were water quality impr ovements that in categories that are linked to serious health concerns such total nitrogen.

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1 37 Additionally, a cost analysis was provided in the article by Solis, Durham, and Ramaswami (2012) that showed a reduction in cost spent on materials alone if pe rvious concrete is used in infrastructure projects (approximately 803RS [$17.81] per cubic meter [614 RS/yd 3 or $13.62/yd 3 ]). However, compressive strength results were variable. The standard deviation by 28 days was about 4 MPa (588 psi). At this stage in the project a field installation could not be recommended because the design strength was not achieved. Although, the strength did fall within the possible strength range (3.5 MPa to 28 MPa [500 psi to 4000 psi]) indicated in the literature by Tennis, Leming, and Akers (2004). There is currently no literature that compares the compressive strength of pervious concrete cylinders and cubes. Since no cylinders were tested in Rajkot it would be beneficial to determine whether the cubes had reached design compressive strength at least by applying a factor relating the compressive strength to cylinders. This is important, since testing standard requirements use different geometries of specimens. Propagation of fractures and types of failures also be come important when different geometries are tested under compressive strength (del Viso, Carmona, Ruiz, 2007). In Phase II laboratory testing it was desired to develop a compressive strength relationship between cubes and cylinders. In phase I testing a relationship was not established when it was realized that the cube strengths oddly resulted in smaller values compared to the cylinders. However, it is good to note that within Mixture 1 the cube compressive strength standard deviation was very close to that calculated for Rajkot cubes (what will be called Mixture R). Phase II is discussed within the next section.

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138 4.3.1 Batching and Curing Phase II Laboratory Samples The author decided that two more pervious concrete mixtures would be sufficient in u nderstanding the relationship between cubes and cylinders for compressive strength, porosity, and hydraulic conductivity however, with the main focus on compressive strength. Additionally the testing between cubes and cylinders would help identify why a h igh standard deviation in strengths for cubes was occurring (i.e. was it due to batching errors, shape of the sample, etc?). Overall the curing process involved removing the samples from the molds after 1 day of curing, similar to the samples made in Rajk ot. The samples remained in a water bath until the day of testing. Samples were tested at 7 and 28 days of curing. Table 4.1 5 shows the mixture proportioning for Mixture 3 (M3) and Mixture 4 (M4) and summarizes all mixture proportioning for the prev ious mixtures It was based on the same mixture design as M2 and MR. The main differences in the design arise from specific gravity and absorption capacities. Table 4.16 lists the specific gravities and absorption capacities of the material. Similar to Phase I and Rajkot testing the design strength was 13.8 MPa (2000 psi). Table 4.15 Mi xture Proportions for Phase II Laboratory T esting

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139 Table 4.1 6 Specific Gravities and Absorption Capacities in Phase II T esting Constructing the small demonstration of a pervious concrete system helped to visualize the process of batching concrete in Rajkot, India. For example the aggregates are separated in piles by sizes. Therefore, the 20 mm (0.79 in), 12 mm (0.47 in), and 10 mm (0.39 in) coarse aggregate are in separate piles. The fine aggregate is in a separate pile as well. Sieve analysis equipment is not available on site. Additionally, sometimes only the 10 mm (0.39 in) or 12 mm (0.47 in) aggregate is available on site. For the pervious concrete demonstration 20 mm (0.79 in), 12 mm (0.47 in), and fine aggregate were available. In order to use an appropriate proportion of 20 mm (0.79 in) and 12 mm (0.47 in) aggregate a mixture design was found for a road project in Rajk ot. The road project used about 59% 20 mm aggregate of total coarse aggregate and 41% 10 mm (0.39 in) aggregate of total coarse aggregate (CII, NRC, and Ambuja Cements, 2004). These same percentages were used for the pervious concrete project and the 10 mm (0.39 in) aggregate was replaced with the 12 mm (0.47 in) aggregate. A sieve analysis was simulated for the aggregate used in the pervious concrete since a sieve analysis was provided for the road project reference. Figures 4.29 a through d compare a sieve analysis between the aggregate used in Phase II and the pervious concrete demonstration in Rajkot.

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140 (a) (b) (c) (d) 1in = 25.4 mm Figure 4.29 Sieve A nalysis (a) P hase II Coarse Aggregate, (b) Rajkot Coarse Aggregate, (c) Phase II Fine Aggregate, (d) Rajkot Fine A ggregate From the sieve analyses in Figures 4.29 and 4.29 b, Rajkot aggregate does not contain as many fines as the aggregate does in Phase II testing. The fine aggre gate gradation in Rajkot is comparable to Phase II testing except the size of the fines in Rajkot may be slightly larger than that in Phase II testing. Figure 4.30 shows the difference in shape between the coarse aggregate available in Rajkot and availabl e in Phase II testing. aggregate has a mix of angular and rounded aggregate. According to Tennis, Leming and Akers (2004) pervious concrete with rounded aggregate tend to have greater compressive strengths than pervious concrete with irregularly shaped aggregate yet irregularly shaped aggregate are still good for achieving desired compressive strengths.

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141 Note: Phase I testing used the same aggregate as Phase II. There was just a small difference in specific gravity and absorption capacity between Phase I and II. Figure 4.30 Coarse A ggregate (a) Rajkot (b) Phase II The shape of the aggregate becomes important in various properties of the pervious concrete. Irregularly shaped aggregate can affect the pores of the concrete which in turn can affect the compressive strength, porosity, and hydraulic conductivity (Sisavath, Jing, and Zimmerman, 2001; and Mahoub, et al., 2009; Neptune, and Putman, 2010). Aggregate gradation could be a clue to the performance of a pervious concrete mixture design (Neptune and Putman, 2010). According to Neptune and Putman (2010) as gradation became well graded the strength increased but the porosity and permeability decr eased. 4.3.2 Sample Shape Effects on the Compressive Strength of Pervious Concrete The average compressive strength of the pervious concrete specimens made for the small demonstration in Rajkot, India was less (1241 psi [8.6 MPa]) than the design strengt h of 2000 psi (13.8 MPa). From research, it is commonly assumed that the ratio between cube and cylinder strengths for conventional concrete is 1.25 (Mindess, Young, & Darwin, 2003). The 1.25 ratio applied to the average Rajkot specimen strength at 28 da ys results in a cylinder strength equal to 992.8 psi (6.8 MPa). However, the laboratory (a) (b)

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142 tests performed in Phase I suggested that the 1.25 strength relationship does not apply to pervious concrete. From Figure 4.36 M1 and M2 produced cylinder strengths about 48% and 57%, respectively, higher than cube strengths. In that case the cube to cylinder strength ratios could be 0.52 and 0.43. These ratios suggested that the Rajkot cube samples would be 2386 psi (16.5 MPa) and 2886 psi (19.9 MPa) as cylinders s trengths. In this phase of the study the influence of the shape of the specimens is investigated in order to assess whether there is a common relationship between cube and cylinder pervious concrete properties. Ultimately a strength factor would help def ine whether the strength of the cubes made in Rajkot, India represented a similar strength tested from cylinders made in the U.S. using the same mixture design but having different material constituent properties. Background on Testing for Compressive Str ength on Cubes and Cylinders The loaded ends of concrete specimens in a compression test experience friction from contact with the platens which introduces a lateral confining pressure near the specimen ends. The ends of the specimen will try to laterally expand while the platens restrain this expansion due to the platens (usually being steel) having a higher modulus of elasticity and P Shearing and compression stresses are present over the surface of the specimen as a result of friction. With an increase in distance away from the top surface the shearing stress will decrease and lateral expansion stresses increase. The specimen will br eak such that the top and bottom of the specimen will form into a cone or pyramid approximately in height (where d is the lateral dimension of the sample). The cone or pyramid is a result of the restraint and can influence the result of true strength Some research has

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143 shown that a height to lateral dimension ratio approximately equal to 2 is suitable for determining true compressive strength. In this study the (h/d) cylinder is equal to 2 while the (h/d) cube is 1.0. Generally for h/d values less t han 1.5, the strength correction factor is less than or equal to 0.97; this can also depend on the design strength of the concrete. High strength concrete is less affected by h/d ratio. However, compressive strength tests on low strength concrete and h/d ratios less than 2 can over estimate strength (Neville, 1973). A cylinder is loaded such that the direction of force applied is perpendicular to the cast layers. However, for a cube, the load is usually applied parallel to the cast layers as a result of having to test a plane surface. If the properties of the different layers are not the same, a layer with a low modulus of elasticity will be susceptible to deformation before any of the other layers. If the platen can change inclination during compressive testing then the failure of the cube specimen can occur when it reaches the strength of the weaker layer (Neville, 1973). In this particular study this is important to keep in mind because the testing machine used allowed for the platen to cha nge inclination during testing. Also it is critical to note that the information on compressive strength of cylinders and cubes has been a result of research on conventional concrete and not pervious concrete Fracture patterns In Figures 4.31 and 4.32 ex amples of how the samples fractured, during compressive strength testing, are shown. During testing vertical cracking, as was seen in Phase I testing, was present in Phase II testing. However, as the samples were removed

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144 from the compression machine the shape of the final sample was usually an hour glass shape for cubes or cone for cylinders. (a) (b) Figure 4.31 Compressive S trength Fractures for M3 (a) C ubes and (b) C ylinders (a) (b) Figure 4.32 Com pressive Strength Fractures for M4 (a) Cubes and (b) C ylinders In some cases the failure of the cylinders had the appearan ce of curvature (see Figure 4.32 ) and this is most likely explained as the fracture path following the cement paste bond around the aggregate. Some fra cture also occurred through aggregate emphasizing a good bond between cement paste an d the aggregate (See Figure 4.33 ). Based on these failure patterns and comparing them to ASTM C39 the patterns do not seem out of the ordinary to conventional concrete.

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145 Figure 4.33 Fracture T hrough A ggregate 4.3.3 Comparing Compressive Strength Results Tables 4.17 and 4.18 show the results of compressive strengths for M3 and M4. From Tables 4.17 and 4.18 it is important to note that only M3 samples (both cylinders and cubes) reached design strength 13.8 MPa (2000 psi). It was promising that the design strength was reached at 7 days of curing. However when tested at 28 days of curing the cylinders failed to reach, much less pass the design strength. The cubes howe ver, had higher strengths at 28 days with the exception for one M3 sample. M4 samples did not reach design strength at any of the testing days. Additionally during Phase II, the cubes tended to have higher strengths than cylinders. Table 4.17 Compressi ve S trength R esults for M3

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146 T able 4.18 Compressive Strength R esults for M4 To summarize Phase I, Rajkot, and Phase II results, Figure 4.3 4 shows the average compressive strength results for M3 and M4 alongside the average results for M1, M2, and MR. All testing results ranged between 6.8 MPa (1000 psi) and 16.4 MPa (2380 psi). Based on the average compressive strength results cube and cyli nders take turns in having higher strengths and this relationship between cubes and cyli nders can be seen in Figure 4.35. From Figure 4.35 only at 7 day testing can a linear relationship be seen for M1, M3, and M4. By the final day of testing (i.e. 15, 2 3, or 28 days) half the mixtures showed cubes with higher strength and the other half with cylinders having higher strengths. Figure 4. 3 4 Average C ompressive S trength of Cylinders and Cube M ixes for P ervious C oncrete D e signed for 2000 psi (13.8 MPa) S trength 1 MPa =145.038 psi

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147 Figure 4.3 5 Relationship between Cylinder and C ube Average C ompressive S trength s Table 4.19 summarizes the cylinder to cube compressive strength ratio. The ratios emphasize the variation in strength res ults. The ratios range from 0.71 to 2.34. Table 4.19 Cylinder to Cube Strength Ratio Based on Average Compressive S trengths Based on standard deviations ranging between 0 and 4 MPa (580 psi), 7 day and final testing day results, and based on a compa rison of cylinder to cube strength ratios it was decided that a t test would not be necessary to try to determine if cylinder and cube means (for compressive strengths) are REL IABLY different from each other.

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148 If a t test was to be performed, 7 day and 28 day strengths would have to be analyzed separately throughout the statistical analysis because strength was expected to change between these days. In other words the mean compressive strength was considered to be moving and the pattern of whether cylin der or cube strengths being higher could change as long as the specimen was allowed to cure. Therefore it would be necessary to treat 7 and 28 days as two separate tests. However, from Figure 4.36 the number of samples in each batch (M2 through MR) has 3 or less samples per testing day It was desired to increase the number of samples for a t test analysis so all cylinders and cube results were combined for 7 day and final da y strength results. Figure 4.37 shows the average compressive strength results f or all cylinders and cubes at 7 day and final day compressive strength testing. Figure 4.36 Average Compressive S trength with Standard D eviation s for All B atches

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149 Figure 4.37 Average Compressive Strength with Standard D eviation s between Cylinders and Cubes at 7 day and Final Day Testing for all B atches 4.3.4 Discussion of Standard Deviations and Population In order to understand the influence of the standard deviations, the standard deviations calculated from the data w as compared to other pervious concrete studies. At the beginning of this chapter it was indicated that the mixture designs would be based on data for compressive stren gth results. Standard deviation was reported for three types of mixtures with ordinary portland cement (OPC), OPC and air entraining admixture, and OPC results with t he res ults of this study. Figure 4.37 provides a summary of average differing estimated air content. 1 MPa = 145.04 psi

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150 It was determined from Figure 4.3 7 that there was no statis tically significant results showing that cube or c ylinder strength would be different In other words, Figure 4.3 7 shows that t he standard deviations overlap, therefore a t test is not necessary to determine significant differences between cylinders and c ubes. 1.3 MPa (188.5 psi) standard deviation at 56 days of curing for 100% OPC concrete cylinders. For this study, all cylinders combined have a maximum standard deviation of about 2.6 MPa (377 psi) for 7 day testing and 3.6 MPa (52 7 psi) for final day testing. Cubes have standard deviations equal to 2.9 MPa (422 psi) at 7 day testing and 3.8 MPa (561 psi) for final day testing. That means this study provides a minimum standard deviation difference of about 1.3 MPa (188.5 psi) comp However, it is also important to keep in mind that Hager used a uniform size of aggregate in the batching which could help reduce standard deviation. Based on this data and the illustrated standard deviations it appears as th ough more samples should be tested to determine if the standard deviations can be reduced. 4.3.5 Summary of Percent Porosity Fi gure 4.38 shows the sum mary of percent porosity determined for all batches. The percent porosity reveals that at least one percent porosity test from each batch fell within the typical range reported Tennis, Leming, and Akers (2004). Except for one batch (M3) the average percent porosity falls below the range.

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151 Figure 4.38 Summary of Percent Porosity for A ll B atches 4.3. 6 Summary of Hydraulic Conductivity The hydraulic conductivity was measure using Delatte, Mrkajic (2009 and 2007) device. As mentioned in a previous section the device was correlated with falling head measurements in order to determine an empirical formula for using the drain time to calculate hydraulic conductivity. Using the drain ti mes for each sample tested from each batch the hydraulic conductivity reveals that from M2 there were two instance where the hydraulic conductivity was representative of a moderately impervious batch which occurs at about 0.15 cm/s. However the other two hydraulic conductivities calculated for M2 revealed that they were much higher than 0.15 cm/s. It is not clear how Delatte et al. method takes into account surface area, because the falling head test does. Using the falling head test criteria alone demon stration a much different curve comp ared to that shown in Figure 4.39 For example the drain time was determined on cube, cylinder, and larger flat surfaces. Figure 4.4 0 shows the hydraulic conductivity calculate using the falling head equation directly.

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152 Figure 4.39 Summary of Hydraulic Conductivity for all Batches Figure 4.4 0 Summary of Hydraulic C onductivity for all Batches Using Falling H ead Criteria 4. 4 Summary The purpose of this study was to determine environmental and structural properties of a pervious concrete demonstration. Changes in rain events can become an issue for stormwater solutions so f loods are a concern for water quality, capacity and long term durability of stormwater designs The pervious concrete demonstration revealed that Rajkot materials made a pervious concrete batch having p orosity and hydraulic conductivity that either passed or met criteria. The pervious concrete also

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153 showed the w ater filtering capabilitie s and potential for reducing some polluting do increase due to the lime present in concrete. Additionally, the l ong term performance of strength was determined uncertain (on average) C ubes only met design strength once out of 4 batches, cylinders m et design strength once out of 3 batches, and through a comparison of standard deviations it was realized a strength relationship between cub es and cyl inders would not be able to be determined and standard deviations between strength results should be reduced In pervious concrete literature gradation becomes important for permeability and strength relationships. Although this dissertation does not mak e a strength and permeability relationship it is good to note that research by Neptune and Putman (2010) showed that as gradation became less uniform or single sized and more well graded the strength also increased, whereas the porosity and permeability de creased. In this dissertation the pervious concrete had well graded aggregate. In research performed by Mahoub, Canler, Rathbone, Robl, and Davis (2009) the pervious concrete permeability and strength did not have a direct correlation, however the degree of compaction for lab specimens and field pervious concrete slabs are not accurately correlated. Their research revealed that the strength of the specimens compacted by using a pneumatic (air pressure adjustable) static press correlated well with field c ored samples. In this dissertation the lab pervious concrete samples were compacted with a roller such that at least 2.5 lb/in was applied to the surface of the samples. However, in the literature by Mahoub et al. (2009) the pneumatic press applied at le ast 8 lb/in and the cylindrical samples as well as cored samples reached at least 6.9 MPa (1000 psi) by 28 days of curing. In this dissertation using roller compaction the samples also reach at least

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154 6.9 MPa (1000 psi) or greater. It is the opinion of th e author that a strength relationship is necessary for cross co untry comparisons of strength since it is unclear which shape is more appropriate for representing strength for pervious concrete no standards exist for testing compressive strength of perviou s concrete, and there was much variability in compressive strength seen in both data presented for cyli nders and cubes in this study.

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155 5. High Volume Fly Ash Concrete for Hot Weather Conditions: Structural and Durability Tests 5.1 Literature Regarding Fly Ash U se in India 5.1.1 Properties of fly ash Published research on the properties of fly ash concrete presumably first appeared in a study by R. E. Davis, Carlson, Kelly, and H. E. Davis in 1937 (Federal Highway Administration [FHWA], 1999). The study confirmed fly ash as a type of artificial pozzol anic material. Thus, fly ash possessed properties similar to volcanic ash, a pozzolana (a siliceous or siliceous and aluminous material having little to no cementitious value but in the presence of moisture and calcium hydroxide will react to form cementi tious properties [ACI 116R,1996] ) used in ancient Rome. The study proved that fly ash contributed to concrete strength, could potentially replace cement up to 50%, had slightly higher later age strengths than ordinary portland cement concrete, exhibited greater plastic flow than portland cement concretes under sustained loading, and had a lower heat of hydration (Davis et al., 1937). Fly ash is a complex heterogeneous material sometimes having two independent and/or a union of two main types of phases w hich make it difficult to characterize fly ash (ACI 232.2R, 1996). 60 to 90 percent of total fly ash mass can be classified as an amorphous (glassy) phase and the other fraction of total mass is a crystalline phase. ASTM C 618 provides a method for classi fying fly ashes through bulk chemical composition. A typical chemistry analysis reports percentage of SiO 2 (silicon dioxide or silica), Al 2 O 3 (alumina), Fe 2 O 3 (ferrous oxide), CaO (calcium oxide), MgO (magnesium

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156 oxide), Alkalies (Na 2 O [sodium oxide] equi valent), SO 3 (sulfur trioxide) and Ignition Loss (unburnt carbon content). If the sum of SiO 2 Al 2 O 3 and Fe 2 O 3 is greater than 70% the fly ash is a Class F and if the sum is less than 70% it is a Class C. Fly ashes usually contain some lime thus their c ementitious value will vary even without the addi tion of calcium hydroxide from p ortland cement. Thus from the chemical analysis a Class C fly ash will have 20% or more CaO content. There are differences in chemistry for fly ashes from country to country Table 5.1 shows an example of chemical compositions of fly ashes from different countries. However, a chemical composition neither address es reactivity nor long term performance when the fly ash is used in concrete (ACI 232.2R, 1996). According to Ma lhotra and Mehta (2008) the chemical differences are not as important as the mineralogical (glassy and crystalline phases) and granulometric (particle size and shape) differences. Nevertheless most countries only perform a chemical analysis on fly ash. Table 5 1 Example of Chemical Composition of Fly Ash from Different C ountries (Malhotra & Mehta, 2008) The glassy phase, which is dependent on the calcium content, highly influences the pozzolanic activity of the fly ash. The high calcium fly ashes are more reactive than low calcium fly ashes. Easily reactive glass and crystalline minerals include calcium

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157 aluminosilicate glass, tricalcium aluminate, calcium aluminosulphate, anhydrite, and free CaO which is present in the high calcium fly ashes. Th e high calcium fly ash will have cementitious and pozzolanic properties. Low calcium fly ashes have aluminosilicate glass which is slightly reactive. The reaction of fly ash with cement mainly depends on the breakdown of the glassy phase by hydroxide ion s and heat from the early hydration of cement. Calcium silicate hydrate (CSH) forms as calcium hydroxide is consumed from The shape of the particles is spherical thus the shape provides a positive effect for the workability when used in concrete mixtures. 5.1.2 Fly ash Consumption in India Data regarding fly ash use in India is not easily assessable Currently, a strong organization such as the American Coal Ash Association does not exist in India that keeps record of fly ash use. However, some literature has reported fly ash use in India. In 2005 112 million tonnes (123 short tons) of fly ash was produced by thermal power plants in India (Dhadse, Kumari, Bhagia, 2008). Fly ash benefits are recognized as reducing heat of hydration in mass concrete, preventing alkali damage, saving 11% in cement manufacturing costs, and improvement in concrete stren gth at later ages for even high dosages of fly ash concrete (Dhadse et al., 2008). The consumption of fly ash in India has improved since the 1994 levels. In 1994 3% of production was utilized versus 38% in 2005 (See Table 5.2). Industrial and construct ion activities in India recognize the benefits of using fly ash. As mentioned in Chapter 1 fly ash in concrete is known for its benefit in reducing the heat of hydration in comparison to ordinary portland cement (OPC). In fact Indian cement industries pr omote the use of their blended cements (i.e.

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158 portland pozzolana cement having fly ash) for reduced heat of hydration. The government has made initiatives in promoting fly ash use in bricks, agriculture, and in water and waste water treatment plants. Tabl e 5.2 shows the percentage consumption of fly ash by certain industries or sectors in India. Table 5. 2 Year 2005 P roduction and U tilization of Fly A sh in India *as a percentage unless noted otherwise Source: Dhadse, Kumari, Bhagia, 2008 Fly ash, in India, is labeled a hazardous material, but the government still encourages beneficial use. It is considered hazardous due to its potential to pollute the air and water if not properly disposed. In addition, it is consider hazardous because it can settle on the leaves of crops that surround power plants thus lowering crop yield. Disposal usually requires slurry ash ponds that experience surface runoff during rain events so salts and metals leach into the groundwater (ENVIS Centre et al., 2007). Disposal costs usually range between Rs 50 100 ($0.90 to $1.78) per million tonne. The cement industry is the largest consumer of fly ash including the hazardous material called blast furnace slag. Since the cement industry is a major user of railways, the R ailway Board in India is considering developing a policy for the movement of fly ash which would require investments in infrastructure facilities at loading and unloading

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159 points (CMA, 2010a). During the 2009 year the Ministry of Environment and Forests is sued new notifications (No.S.O. 2809) regarding fly ash, that the cement industry believed would seriously impact operations (CMA 2010a). Before the notification, fly ash was available to end users (i.e. cement industry) without requiring payment except f or transportation cost. W ith the new notifications cement manufacturers were no longer exempt from having to pay for the use of fly ash. Another clause in the notification stated that fly ash must be used if within 100 km (62.1 mi) radius of a thermal po wer plant. The cement industry felt like this statement restricted the use of blast furnace slag which can be used for higher replacements of clinker (up to 65% for slag versus 35% for fly ash) (CMA, 2010a). Within this study the use of fly ash in buil dings and pavements is encouraged for cities. Cities such as Rajkot, India have experimented with high volume fly ash (HVFA) concrete and have been successful in attaining good strength as was discussed in Chapter 2. A local structural engineer, along w ith the city of Rajkot, had an interest in experimenting with other sources of fly ash. In 2004 the HVFA road project included the use of fly ash from the Sikka thermal power plant. However, fly ash is also available from the Vanakbori and Gandhinagar t hermal power plants and it was desired to use these fly ashes for this study. The following section presents the experimental study that involved the use of two additional sources of fly ash and presents the data regarding fly ash properties and compressi ve strength. 5.2 Literature on HVFA C oncrete for H ot W eather C onditions Testing OPC concrete and concrete with cementitious materials, such as fly ash, under hot weather conditions has resulted in several published literature. In example Schindler

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160 (2004 ) presents a model to account for the effect of temperature on the rate of hydration when different cement types and mineral admixtures are used. The model, called activation energy model, is a function of the cement composition, and type of mineral admix tures used in the entire mixture. The model is created using a nonlinear regression analysis. In work by Zhang, Shen, Zhou, and Li (2011) compressive strength and tensile strength development for fly ash concrete samples exposed to thermal environments i s explained. Both tensile and compressive strength increases with increasing curing temperature when concrete samples contain fly ash. Thus their work implied that appropriately increasing curing temperature could improve the compressive and tensile stren gth of fly ash concrete but not OPC concrete samples specifically made with a w/c ratio of 0.3. However, curing occurred in steamed heated conditions for 6 hours and then samples were placed in room temperature for 2 months. In research by Khoury (2006) shrinkage, creep, and expansive strains in previous cured plain concrete exposed to heat were shown to be dependent upon temperature cycles. However, temperatures ranged 110oC to 600oC to represent nuclear reactor concrete. Nevertheless the paper reveale d that the long term durability of the concrete is dependent on the aggregate type, the age of the maturity of the concrete, and the thermal loading cycles. Within this dissertation, however, the literature provided throughout this dissertation pertains s pecifically to the performance of HVFA concrete in heated conditions below 65.6oC (120oF) Hot weather is defined as high ambient temperatures (sometimes above 26.7 o C [80 o F]) with any combination of high wind velocity, low relative humidity, and exposure to solar radiation (PCA, 2002). Hot weather is detrimental to fresh concrete because it can increase water demand, accelerate slump loss, increase the rate of setting, inc rease

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161 risk of plastic and thermal cracking, affect entrained air, and increase strength loss over long term due to increases in internal concrete temperatures (PCA, 2002). Hot weather effects on hardened concrete have been identified as decreasing strengt h, decreasing durability from cracking, increasing permeability, and increasing risk for drying shrinkage (PCA, 2002). Studies have shown the importance of cooling materials before mixing, batching and placing concrete during temperatures greater than 85 o F and publishing these suggested guidelines in books such as the PCA manual (2002) and ACI 305 (2010) Other studies have subjected concrete samples to hot weather conditions and have included usually one of following variables: Humidity in the range of 65% to 100% (Ravina, 1981; Mehta, 2002) Including fly ash at percentages between 30% to 75% (Ravina, 1981; Mehta, 2002; Senthil & Santhakumar, 2005; Bentz, Peltz, Herrera, Valdez, & Juarez, 2010). Testing in temperatures up to 40 o C (104 o F) (Ravina, 1981 ) Testing with heated materials such as increasing aggregate temperature up to 70 o C (158 o F) (Mouret, Bascoul, Escadeillas, 1997) Each of the studies that included one of the testing variables above produced information about what to expect in terms of comp ressive strength. The studies indicated that design compressive strength could decrease anywhere between 5 and 15%. But, the studies used different testing variables under heated conditions, thus it was not clear which of the testing variables, including the heated conditions, could be affecting the results of the compressive strength more. Additionally, certain studies were unique and should be

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162 investigated further. For example, Villarreal & Torres (2002) not only subjected their concrete samples to he ated conditions they cured the samples for a period of 6 months under dry conditions and mimicking shading. This study is unique because it might be used to represent a climate change effect where extreme temperatures occur over long periods of time. Ho wever, the samples contained a mix of high volume fly ash (up to 53% fly ash), and silica fume. So any benefit towards compressive strength may not be attributed to the fly ash alone. The study by Mouret, Bascoul, Escadeillas (1997) is one the very few s tudies that tests the effect of heated aggregate to concrete while mixing and curing. However, the concrete samples only include ordinary portland cement and the samples were initially cured in hot weather conditions for only 24 hours. Based on the lite rature there is a lack of tests on HVFA concrete in semi arid to arid conditions, with heated aggregate, and curing above 37.8 o C (100 o F). Additionally two other testing variables that have not been used in hot weather testing have been aggregate content a nd curing in cyclic temperatures to simulate the thermal gradients that arise during the changes between day and night. Goal of HVFA concrete in hot weather conditions Study Overall the goal of this portion of the dissertation was to evaluate HVFA concrete Objectives for the Study The overall objective to reach this goal was to determine the structural and durability benefits that arise from HVFA in concrete mixtures when subjected to hot weather conditions.

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163 This study was unique because it combined many of the testing variables from the literature review for a more holistic approach to testing HVFA concrete in hot weather conditions. The following testing variables were used: Cement or 50% fly ash Heated or no heated aggregate (Temperatures around 65 o C [149 o F]) Curing in ideal (water) or dry heated conditions (above 37.8 o C [100 o F]) Curing for 90 days Changing the aggregate content to 55% coarse aggregate or 65% coarse aggregate of total aggregate weight. A lso the heated curing conditions were set up to simulate cyclic temperatures (or the thermal gradient that occurs between night and day). This condition is discussed more in detail in the methods section. Also the aggregate content was varied because dry ing shrinkage was identified as a problem in hot weather conditions and has not been thoroughly discussed in any of the literature found for this dissertation. PCA (2002) does indicate that the shrinkage is best minimized with a low water content. A low water content is achieved by using a high coarse aggregate content. Additionally, PCA indicated that supplementary cementing materials will have little effect on the shrinkage if used in small dosages. Therefore, it was worth exploring the effects of a h igh dosage of fly ash on shrinkage combined with two different aggregate contents. Also unique to this study is the combination of testing methods to quantify major changes in HVFA concrete samples cured in hot weather conditions. Most literature re ferred to compressive strength to quantify the effects of testing in hot weather conditions, but within this study permeability, length change, and modulus of elasticity

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164 were also measured. Additionally, it was important to this study to test specimens fr om 56 days beyond because the age of strength acceptance for HVFA concrete should be extended to 56 or 90 days (HR, 2005). 5.3 Phase I study for HVFA in Hot Weat her Conditions: India and U.S. C omparison of Fly Ash Properties (Fly Ash U sed in Rajkot, Gujarat, India and Denver, Colorado, U.S.). The tests involving HVFA concrete under extreme hot weather conditions could not be performed in Rajkot, India. Instead, two sources of fly ash from thermal power plants near Rajkot were tested in HVFA concrete mixtures for compressive strength. Rajkot Municipal Corporation and Lakhlani Associates were interested in the compressive strength benefits that these two sources of fly ash could potentially provide, thus the reason for using these sources of fly ash. The fly ash came from the Vanakbori and Gandhinagar power plant located approximately 302 km (187.7 mi) and 258 km (160.3 mi) away from Rajkot, respectively. Figure 5.1 shows the two sources of fly ash. In Figure 5.1 it appears as though the Vanakbori f ly ash has a lighter grey color compared to the fly ash from Gandhinagar. The goal for testing these two sources of fly ash was to develop a compressive strength relationship with the U.S. source of fly ash. Very similar to the method used in Chapter 4 f or the pervious concrete, concrete cubes made in Rajkot were tested for compressive strength and finally compared to the concrete cubes and cylinders made in the U.S.

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165 Figure 5.1 (a) V anakbori F ly A sh, (b) Gandhinagar Fly A sh In Table 5.3 the chemical analysis for the different fly ash sources are presented. Class C fly ash is provided, to show what lime contents levels have to be in order to be classified as Class C fly ash. Since the Indian sources of fly ash had very low l ime contents their reactions with cement would be closer to that of a U.S. Class F fly ash. Class F fly ashes have less of a cementitious reaction compared to a Class C fly ash and are therefore dependent on the reaction with the lime (calcium hydroxide) in cement to make hydrated calcium silicate (which provides strength to the concrete). Additionally, the concrete strength gain for Class F fly ash is slower than if Class C fly ash is used. Table 5.3 Chemical A nalysis for Various Fly A sh S ources between the U.S. and India (a) (b)

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166 In Rajkot, two batches of concrete were mixed, with each batch having 50% replacement of cement by fly ash. Batching and placing concrete in the molds followed BIS 516. One batch contained fly ash from the Vanakbori thermal power plant and the other batch contained fly ash from the Gandhinagar thermal power plant. Table 5.4 presents the mixture design for both batches. While placing the concrete in the cubes the Gandhinagar fly ash exhibited slightly more flowability than t he Vanakbori batch. Both batches were made using the same amount of materials. The difference in flowability may have been due to the differences in fly ash, but may have also occurred from the moisture trapped within any of the material since moisture c ontent was not determined (i.e. dry material was used but some sand may have been moist just from observation of the material out in the field). Or the method of adding water to the batch may have not been consistent (i.e. water was added using a 1 liter bottle and any fraction of water that was needed was estimated from the 1 liter bottle). Figures 5.2 and 5.3 show the two concrete batches before placing into the cube molds and after placement into the molds. Table 5.4 Mixture Proportions for HVFA Concrete in Rajkot 1 kg/m 3 = 1.68554 lb/yd 3 Three 15.2 cm (6in) cube specimens from each batch were tested for compressive strength after 7 days and 28 days of curing. Figures of the compressive strength and fractures paths are shown in Appendix D (Fi gures D.1 through D.2). A 56 day testing could not be performed because not enough molds were available on site where the

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167 batching occurred. In Table 5.5 the compressive strength results as well as standard deviations are shown. Figure 5.4 graphs the co mpressive strength results. (a) (b) Figure 5.2 Batches (a) Vanakbori and (b) Gandhinagar (a) (b) Figure 5.3 Cubes (a) Vanakbori and (b) Gandhinagar Table 5.5 Compressive Strength Results for Rajkot HVFA Concrete Samples 1 MPa = 145.038 psi

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168 1 MPa = 145.038 psi Figure 5.4 Average Compressive Strength Result for Rajkot HVFA Concrete Samples The design compressive strength was 27.6 MPa (4000 psi). The compressive results reported in Table 5.5 and Figure 5.4 demonstrate that the Vanakbori samples gained strength more quickly compared to the Gandhinagar samples. This might be explained by the slightly higher lime content that Vanakbori fly ash had according to the Table 5.3. By 28 days at least one sample from each batch reached design co mpressive strength. However, average compressive strength results demonstrate show that the samples are about 9% less than the design compressive strength. The batching of the HVFA concrete samples using the U.S. Class F fly ash from Craig thermal power plant followed the same mixture proportions used in Rajkot but involved the use of ASTM standards. Table 5.6 shows the mixture proportions. The aggregate content for the U.S. mixture differed because specific gravities differed compared to those assumed for the aggregate available in Rajkot. Two 15.2 cm (6in)

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169 cubes and two 10.2 cm x 20.3 cm (4 in x 8 in) cylinders were made for 7, 28, and 56 day testing. Slump, unit weight, and air content were measured for the samples batched using the U.S. fly ash source (See Table 5.7) while these measurements could not be made for the Rajkot HVFA batches because equipment was not available. Table 5.6 Mixture Proportions for HVFA Concrete in Denver 1 kg/m 3 = 1.68554 lb/yd 3 Table 5.7 Fresh Concrete Prop erties for the HVFA Concrete Batch in Denver The unit weight is very close to a normal weight concrete of 2403 kg/m 3 (150 lb/ft 3 ). The slump is low and is mainly due to no use of admixtures however, the concrete remained workable throughout the batchin g and molding process. The estimated air content was within 99% of the actual air content. Air entraining admixtures were not used in either one of the HVFA batches because high air contents are mainly preferable to resist freeze/thaw effects. In Rajkot freezing/thawing is not a concern. Compressive strength results are shown in Table 5.8 and Figure 5.5. Table 5.8 shows the individual sample compressive strength results. Unlike the Rajkot fly ash samples none of the U.S. fly ash samples reached desi gn compressive strength by 28 days, however, by 56 days of curing all U.S. fly ash samples passed design strength.

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170 Table 5.8 Compressive Strength Results f or U S HVFA Concrete Samples 1 MPa = 145.038 psi 1 MPa = 145.038 psi Figure 5.5 U.S. and India HVFA C oncrete Average C ompressive S trength R esult s Figure 5.5 also provides a comparison of average compressive strength results for the HVFA concrete samples batched in India and in the U.S. By 7 days of curing the cylinders gain more st rength at a faster rate compared to all cubes. However, the Craig (U.S. fly ash) cube strength on average maintains a higher strength value compared to the Vanakbori and Gandhinagar samples. Figure 5.6 shows the average compressive strength results and s tandard deviations for all HVFA concrete samples. This figure provides another method for extracting observational results between all mixtures. For example, at

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171 28 days, based on the trend in average compressive strength and standard deviations, there ap pears to be no statistical significant difference among the various sources of fly ash compared to the U.S. cylinders. This comparison is necessary to assume that hot weather concrete test results gathered from U.S. HVFA concrete would be similar if gathe red from the HVFA concrete made from the Indian sources of fly ash. Therefore, the average cylinder to cube compressive strength ratio reported in Table 5.9 may be assumed valid. Figure 5.6 Summary of Average Compressive Strength R esults and Standar d D eviations between the U. S. and Indian Sources of Fly A sh Table 5.9 Average Cylinder to C ube C ompressive S trength R atios for U.S. and Indian HVFA Concrete M ixtures Gathering the information on U.S. and Indian fly ash relationship revealed that all sources of fly ash are representative of a Class F designated fly ash. The strength results also showed that HVFA concrete made from these three sources of fly ash produce

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172 average compressive strength results with only about a 5% difference. Thus tests regarding HVFA concrete under extreme hot weather conditions were proceeded with using the U.S. Class F fly ash from Craig power plant with the assumption that Rajkot HVFA c oncrete samples would perform similarly with at most a 5% difference. 5.4 Phase II: Properties of HVFA and OPC Concrete When Subjected to Hot Weather Conditions To begin testing HVFA and OPC concrete samples in hot weather conditions, average aggregate t emperatures when exposed to hot weather temperatures were measured in order to determine the average temperatures to be used in the laboratory testing. Also, the benefit of fly ash concrete having a lower heat of hydration was verified through two tests c omparing internal temperatures of HVFA and OPC concrete samples as they cured in ambient and simulated hot weather conditions. 5.4.1 Aggregate Temperatures The PCA (2002) manual provides guidelines for managing material properly during hot weather condit ions. Materials should be cooled or protected enough so the concrete temperatures can ideally remain around 16 to 27 o C (60 to 80 o F) (although ACI 305 does mention the maximum allowable fresh concrete temperature can be 35 o C (95 o F)). As such ready mix com panies, at least in the U.S., accomplish this by shading with silos and sheds (See Figure 5.7), and spraying or fogging with water. However, when spraying, the moisture content of aggregates, before use in a concrete mixture, must be taken into account.

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173 (a) (b) Figure 5.7 Aggregate (a) Storing and Cooling in a S hed and (b) Stockpiling Within this dissertation the author is suggesting that changes in climate could affect the effectiveness of these methods for keeping aggregate cool, especially in countries, where, aggregate is most likely stored on site without shade (sometimes referred to as stockpiling [See Figure 5.7 (b)]). Changes in temperatures can require more use of water in areas that already experience droughts. The availability of ice is already limited in many countries and may not be a priority for concrete. The only optio n for cooling aggregates may be shading, but for regions that already experience hot temperatures shading may not help too much once temperatures pass a certain range. Additionally, moisture content may not be taken into account on a daily basis. On the other hand countries may purposely not cool aggregate by means of water (i.e. dry aggregates are preferred and thus it is ok to assume moisture content is negligible). Aggregate has the greatest mass in a concrete mixture; taking up 60 to 80% of the volum e of a normal weight concrete mixture (ACI, 2010) therefore aggregate can have a great e ffect on the temperature of the concrete and final performance of the concrete mixture while curing and after curing. In countries where stockpiling is common it is

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174 possible that there are cases when aggregate is exposed to weather conditions without use of shading or cooling by water. Therefore, it was decided that for this research it was worth determining what were some of the temperatures aggregate could reach un der hot o C (80 o F)]. For several days from mid July through end of September temperatures of stock piled aggregate were measured and compared to stored or cooled aggregates. Stock piled aggregate temperatures were taken on site a ready conc rete plant in Colorado, U.S. (Company Name: Boral Ready Mixed Concrete Company). Originally the stock piled aggregate temperatures were going to be recorded on location a construction materials company near Phoenix, Arizona (Vulcan Materials Company); how ever, most construction materials companies in hot regions of the U.S. unquestionably cool their aggregate. In this case Vulcan Materials Company in Arizona did record temperatures of their cooled aggregate stored on site and their cement and fly ash stor ed in silos. At Vulcan Materials the aggregates are maintained at cool temperatures by spraying them and keeping them shaded. The temperatures of the aggregate are reported in Figure 5.8 From Figure 5.8 the stored/cooled aggregate remains between a ra nge of 20 to 30 o C (68 to 86 o F) under ambient temperatures of about 40 o C (104 o F). Above an ambient temperature of 40 o C (104 o F), it might be assumed that the temperature range of stored/cooled aggregate would be difficult to maintain between 20 to 30 o C (68 to 86 o F). The temperatures of the stored/cooled aggregate might even reach 30 to 40 o C (86 and 104 o F) in 40 o C (104 o F) weather. On the other hand, stockpiled aggregates can reach temperatures that range between 50 and 75 o C (122 and 167 o F). Stockpiled temp eratures can be almost twice the ambient temperatures. These observations made from Figure 5.8

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175 supports one of the hypotheses of this dissertation (i.e. if ambient conditions can reach high enough temperatures it will be difficult to keep aggregates cool and there could be more demand on energy and resources to keep the aggregate cool). o F = [ o C* (9/5)]+32 Figure 5.8 Temperatures of S tock P iled and S tored/ C ooled A ggregate 5.4.2 Verifying Temperatures of HVFA and OPC C oncrete D uring H ydration A benefit of HVFA concrete is its internal temperature as hydration is occurring during curing. The internal temperatures within HVFA concrete can peak about 57% (w/c 0.53 and 50% replacement of OPC by FA) less than OPC concrete depending on the water cement ratio (Wang and Yan, 2006). In other research the temperature rise in the HVFA concrete was about 36% less compared to OPC concrete (Atis, 2002). The lower heat of hydration minimizes the risk of cracking which is beneficial during concreting in hot weather c onditions. For this dissertation it was preferred that these lower internal temperatures be verified through some trial mixtures. The mixture proportioning is shown in Table 5.10. Trial 1 mixtures were tested under ambient room temperature

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176 conditions wh ile Trial 2 mixtures were tested under hot weather conditions of about 47.8 o C (118 o F). Table 5.10 Mixture Proportioning for M ixture D esigns in Phase IIa Testing of HVFA and OPC C oncrete 1 kg/m 3 = 1.68554 lb/yd 3 Coding: HWC = Hot Weather Conditi ons, T# = Trial number, FA = fly ash, OPC = ordinary portland cement The temperatures were recorded using the CR10x datalogger model from Campbell Scientific (See Figure 5. 9 ). Type J thermocouples from Omega Engineering Inc. were used such that the positive wire was iron and the negative wire was constantan (copper nickel alloy). The insulation around the wires was neoflon (copolymer). The maximum temperature that the wire s could perform in was 200 o C (392 o F). The wires were twisted together. The twisted ends of the wires were then dipped in liquid tape to help keep the wires protected in the concrete while the concrete hardened during curing. It was the decision of the a uthor to take temperatures in the middle of the cylinder samples. Concrete cylinders were made for the temperature testing. For trials 1 and 2 temperature testing, one layer of concrete was placed in the cylinder (about 10.2 cm [4 in] in depth) and was c onsolidated. The wire was then placed about midpoint of this layer and finally the last layer of con crete was placed (See Figure 5.10 ).

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177 Figure 5.9 Campbell Scientific Datalogger (CR 10X) U sed to R ecord Concrete T emperatures Figure 5.10 Installing t he Thermocouple Into C oncrete S ample Figure 5.11 shows the average internal temperatures recorded for HVFA and OPC concrete cured in ambient room temperature conditions. In the Figure the room temperature throughout the curing process is provided. The a verage temperatures are also graphed with standard deviations which are shaded in blue for OPC concrete and pink for HVFA concrete. From the figure it appears as though HVFA concrete peaks at a slower rate compared to OPC and has a peak temperature about 11% smaller than OPC.

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178 Figure 5.11 Internal C uring T emperatures of A mbient C ured Fly A sh and OPC Samples During Trial 1 T esting Figure 5.12 shows the internal curing temperatures when the HVFA and OPC concrete trial 2 samples were cured in heated conditions. The curing temperature of about 47.8 o C (118 o F) was the maximum temperature that was desired for this study because it represented some of the warmest temperatures parts of India have reached in the past 2 years, although Rajkot has had a high temperature of 42 o C (107.6 o F). Under heated conditions the HVFA concrete demonstrated that it has a slower rate of heat gain compared to OPC concre te. The OPC peaked at about 58 o C (136.4 o F) which was about 5% higher than HVFA concrete. Under heated conditions the benefit of lower internal temperatures of HVFA concrete might decrease by about 5%. The percentage difference between HVFA concrete and OPC did not match those reported by Wang and Yang (2006) and Atis (2002) but lower temperatures for HVFA concrete were verified in the both tests. Also a unique characteristic of HVFA concrete was observed during the heat curing. In Figure 5.13 the surfa ce of the concrete samples are shown. The surface of the

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179 HVFA concrete sample develops a glassy sheen compared to the OPC concrete and may be attributed to the amorphous phase present in the fly ash. Figure 5.1 2 Internal Curing T emperatures of H eat C ured HVFA a nd OPC S amples D uring Trial 2 T esting (a) (b) Figure 5.1 3 Surface of Samples after Heat C uring (a) Fly Ash Mixture (b) OPC M ixture

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180 5.5 Phase III study for HVFA in Hot Weather Conditions: Laboratory Testing of Structural and Durability P roperties. The verification of lower internal temperatures for HVFA concrete compared to OPC concrete led to the main phase of the study. Table 5.11 shows the mixture proportion for 16 batches made between HVFA concrete and OPC concrete. The mixture codes are understood as follows: 8 mixtures were not influenced by heated aggregate while the 8 mixtures were. Recall tha t the heated aggregate is meant to represent the possibility of exposing stockpiled aggregate to hot weather conditions or the inability to keep even stored aggregate cool in extreme temperatures. The water cured samples represented ideal conditions and the heat cured samples were cured in temperatures ranging from above 37.8 o C (100 o F) to 47.8 o C (118 o F). Fresh and hardened concrete tests were performed following ASTM standards listed in Table 5.12. At least two samples were used for hardened concrete test except modulus of elasticity and length change. Modulus of elasticity relied on one new sample for each testing day while the length change relied on at least one sample up to 90 days. Ideal (water) curing was accomplished with a water tank where the temperature of the water was around 22.2 o C (72 o F). The wa ter tank is s hown in Figure 5.14 (a). The heated tank was similar to the water tank, customized with bricks (with holes) arranged on the bottom of the tank to allow air to circulate fully around the concrete samples. Two heaters were placed on either ends of the insi de of the tank. The heaters were modified OPC55W Coarse Aggregate Conten t (%) Water (W) or Heat (H) cured Ordinary Portland Cement (OPC) or 50% Fly Ash (FA)

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181 space heaters to continuously heat the tank between 37.8 o C (100 o F) and 47.8 o C (118 o F). Fans were also placed in the tank to allow the air to circulate throughout the curing process. No moisture was added to the t ank nor to the samples once the samples were placed in the tank. The heaters were connected to a timer that allowed the heaters to remain on for 6 hours and turn off for 6 hours. Table 5.11 Mixture P roportioning for HVFA and OPC Concrete Mixture D esi gns in Extreme H ot Weather Condition T esting 1 kg/m 3 = 1.68554 lb/yd 3 Table 5.12 ASTM Standards U sed for F resh and Hardened Concrete T ests

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182 This cyclic heating was meant to represent the thermal gradient that occurs from the temperature shift between night and day. The temperature of the tank when the heaters were off was about 22.2 o C (72 o F). In fact in Rajkot, India summer nights are usually 22.2 o C (72 o F) or warmer. Figure 5.14 (b) shows how the concrete samples were placed in the heated tank. T he concrete samples were also covered with 6 mil polyethylene sheets to represent field curing when trying to maintain prevent evaporation. The heated tank was sealed with aluminum foil insulation and boards to help retain the heat in the tank. Figure 5. 1 5 shows the aluminum and boards placed on the tank. Figure 5.16 is a schematic of the heated tank with dimensions and orientation of the bricks. Two tanks were actually customized to simulated heated conditions and two tanks were used for the ideal wate r curing conditions. The heated tanks had to hold a minimum of 152 samples together and this was similar for the water tanks. (a) (b) Figure 5.1 4 View of (a) Water C uring Tank (i.e. Ideally C ured) and (b) Hot W eather Curing T ank

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183 (a) (b) Figure 5.15 H ot Weather Simulation Tank (a) B oards to Keep Heat in (b) Close U p of Aluminum F oil Bubble I nsulation Figure 5.16 Schematic of Hot Weather Simulation T anks In Phase II I of the hot weather testing internal temperatures were also recorded for the full 90 days of the curing. However, the placement of the wire at midpoint of the concrete layer and half the depth of the cylinder was ensured with better precision by taping the wire at half the distance of a small dowel that had a length of 20.3 c m (8 in). Two cylinders were used to take temperature recordings while the samples cured for 90 days. In this case the CR5000 Campbell Scientific datalogger was used to keep record of temperatures. This datalogger was used because more channels for the thermal couples

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184 were available. Figure 5.1 7 shows a picture of the CR5000 datalogger and its placement between the heated and water curing tanks. (a) (b) Figure 5.17 Campbell Scientific (a) D atalogger (CR 5000) and (b) Setup for the I deal and Hot Weather Simulation T anks for Recording Concrete T emperatures Temperatures of the materials were recorded before mixing and reported in Table 5.13. The concrete temperature was also recorded just after mixing. On average the no heated aggregate OP C concrete mixtures were about 24.4 o C (76 o F) and no heated aggregate HVFA mixtures were 22.7 o C (73 o F). The heated aggregate OPC mixtures were about 32.8 o C (91 o F) while HVFA concrete mixtures with heated aggregate were about 30.5 o C (87 o F). The average tem peratures between HVFA and OPC concrete provide another demonstration how the HVFA concrete will develop lower temperatures over than OPC concrete even with heated aggregate. However, temperature differences only range between 6 and 8%. Thus another ques tion arises whether HVFA concrete can maintain these percentage differences when actually placed in the field. Peak temperatures during the curing process are reported in Table 5.14 for the concrete mixtures without the heated aggregate. Peak temperature s for the concrete mixtures with heated aggregate have yet to be analyzed. But with the no heated aggregate concrete it is verified that HVFA concrete mixtures have lower internal temperatures during hydration.

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185 However, the difference between HVFA temper atures and OPC temperatures increases to approximately 13%. The percentage difference was calculated using the average temperature for all OPC and HVFA concrete mixtures. Tab le 5.13 Material T emperature s Before Mixing (And During Mixing for the Heated A ggregate M ixtures) Table 5.14 Internal Peak Temperatures During C uring

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186 5.5.1 Compressive Strength Compressive strength tests occurred as early as 1 day of curing. The purpose of testing at such an early age was to determine how much of a strength gain concrete samples can gain when the hydration is accelerated from hot temperatures. Early Strength Ga in Figure 5.1 8 shows the early strength gain (average compressive strength results) for the first 14 days of curing. In all cases by 14 days OPC strength is much larger than HVFA concrete strength. If the largest OPC strength (OPC65H) is compared to the smallest HVFA concrete strength (50FA55W) at 14 days for the no heated aggregate results OPC has a strength approximately 2 times larger than the HVFA concrete. Another observation made in the no heated aggregate results is that the two water cured HVFA c oncrete mixtures do not reach design strength by 14 days but the heat cured HVFA concrete mixtures do. The heated aggregate mixtures surprisingly show that the lowest HVFA concrete strength (50FA65W) is only about 37% lower than the highest OPC concrete s trength (OPC65W). However, only one HVFA concrete mixture with heated aggregate pass the design strength by 14 days. It was expected that at least the water cured HVFA concrete mixtures would not reach design strength since their true strength benefits a re usually not expected until 56 days of curing. Later Strength Gain Later strength gain (average compressive strength results) is shown in Figure 5.19 For the no heated aggregate concrete mixtures OPC remains higher in strength compared to the HVFA concrete mixtures. But both the OPC and HVFA heat cured samples show either a decrease or leveling off in strength gain. If peak temperatures are

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187 compare d to final temperatures the following observations are made. OPC concrete samples decrease in strength by as much as 14% when analyzing OPC55H. HVFA concrete samples decrease in strength by as much as 7% when analyzing 50FA65H. The heated aggregate conc rete samples also show a decrease in strength for the heat cured samples. OPC samples decrease by as much as 12% when analyzing OPC65H. HVFA samples decrease by as much as 5% when analyzing 50FA65H. Compressive Strength Results and Standard Deviations F igure 5.20 shows overall average compressive strength results with standard deviations. The standard deviations for HVFA concrete do not overlap standard deviations for OPC concrete expect perhaps by 90 days of testing. Therefore, it is appropriate to ind icate that OPC concrete mixtures performed better than HVFA concrete mixtures in terms of strength when concrete did not contain heated aggregate. In the other case where heated aggregate was involved by 90 days some OPC concrete mixtures do have standard deviations that overlap with the HVFA concrete mixtures. But a t test performed for at least the 90 day strength tests reveal that there are no significant results indicating that HVFA had higher strengths than OPC concrete mixtures. It is important t o note that during the compressive strength testing OPC heat cured samples to have a rapid break once ultimate strength was reached while heat cured HVFA concrete samples tended to break more subtly. The breaking characteristics should be studied in more detail because this could be good indicators of how a structure might fail or deteriorate over time. Also textures of the concrete begin to differ as curing proceeded. Water cured HVFA samples were initially powdery until about 56 days of age. But heat c ured samples for both HVFA and OPC concrete were not powdery until

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(a) (b) Figure 5.18 Early Age Compressive Strength (a) No Heated A ggregate (b) Heated Aggregate 188

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(a) (b) Figure 5.19 Later Age Compressive S trength (a) No Heated Aggregate (b) Heated Aggregate 189

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Figure 5.20 Compr essive Strength Results (a) No Heated Aggregate, (b) Heated A ggregate (a) (b) 190

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191 56 days of age. OPC heat cured samples showed more powdery texture than HVFA samples. Early age heat cured samples had more of a rough texture. Appendix D has Figures showing the different textures and breaking results for some water and heat cured sam ples. 5.5.2 Modulus of Elasticity The modulus of elasticity was measured because it describes the stiffness of the material. The modulus of elasticity is derived from the elastic response of a stress strain curve resulting from compressive strength. By determining the elastic modulus for the concrete samples by as early as 1 day the trend in stiffness is seen. Figure 5.2 1 shows the modulus of elasticity results. By 56 days normal weight concrete should can have a modulus of elasticity ranging betwee n 14 42 GPa (2000 to 6000 ksi) [Mindess, Young, and Darwin, 2003). All mixtures fall within this range of modulus of elasticity. Early age modulus of elasticity for the heated aggregate concrete mixtures show much smaller stiffness for the HVFA concret e samples compared to the concrete mixtures having no heated aggregate. 5.5.3 Resistance to Rapid Chloride Ion Penetration Rajkot, India is located approximately in the center of the State of Gujarat, and is surroun ded by the Arabian Sea from the northwest to the southeast corner of the state. One of the shortest distances to the sea from Rajkot is about 90 km (56 mi). Although Rajkot is not a coastal city, its proximity to the Arabian Sea might lead to the potent ial for salts (sodium chloride) trapped in the surrounding air or in the soil to cause problems to any reinforced concrete. The ingress of chloride ions into concrete can lead to the breakdown of a passivating iron oxide film that surrounds any reinforcem ent that is in the

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(a) (b) Figure 5.21 Modulus of Elasticity (a) No H eated A ggregate Concrete (b) Heated Aggregate C oncrete 192

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193 concrete. The iron oxide film originally develops with the presence of a high pH or alkaline environment created by the concrete. As the pH is reduced from intrusions, such as chloride ions, the electrochemical protection to the steel can break down and the corrosion process will be activated (Detwiler, Kjellesen, & Gjrv, 1991). Elevate d curing temperatures can decrease the strength of concrete and decrease durability properties such as resistance to chloride ion penetration. The rapid chloride permeability test (RCPT) was performed in this study as an indirect method of determining whe ther the pore structure of the concrete was affected while the samples were cured in elevated temperatures and when the temperature of the aggregate was increased. Some authors have described the RCPT as a measure of electric conductivity rather than a me asure of Nevertheless, the RCPT relies on the pore structure of the cement paste matrix and pore solution composition (Jain & Neithalath, 2010). The pore matrix develops as more hydration occurs. With elevated temperatures the hydration products do not evenly distribute causing a coarsening of the pores (Detwiler, Kjellesen, Gjrv, 1991). Figure 5.2 2 shows the permeability apparatus used in this study. Figure 5.2 2 Permeab ility Testing Setup A variety of experimental conditions or compositions used in this study are expected to affect the pore matrix of the concrete samples. These conditions include a)

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194 the use of cement versus fly ash, b) curing in ideal (water/moist) or heated conditions c) changing the coarse aggregate content (of total aggregate content) from 55% to 65%, and d) using no heated or heated aggregates. Each of these conditions are expected to affect the pore matrix as follows: a) The inclusion of Class F fly ash will cause the cementitious properties of the fly ash to react slowly in comparison to OPC. Thus the pores of the cementitious matrix will fill in more slowly. In addition, a 50% replacement of OPC with FA usually requires 56 to 90 days of curing in order to see the benefits of FA which can ultimately increase resistance to chloride ion penetration. b) Water cured specimens should allow for a more uniform distribution of hydration products in comparison to heat curing. Additiona lly, heat curing could cause water within the samples to evaporate too quickly thus leaving larger pores and eventually leading to more microcracking than what would be seen in water cured samples. c) The total aggregate content will not change within the design of the mixture, however the total coarse aggregate content will increase from 55% to 65%. It can be expected that with more coarse aggregate there will be more heat storage especially for those samples cured in heat. With more heat the samples sho uld again experience a non uniform distribution of hydration products and the possibility of weaker interfacial tra nsi tion zones (ITZ) surrounding the coarse aggregate. d) If aggregates are heated, the size and amount of pores within the concrete matrix cou ld increase at a much earlier age than the samples without heated aggregates.

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195 Finally the results from the RCPT test should show that heating the aggregates and curing them in heated conditions could show an increase in permeability by twice that of the s amples without heated aggregates. Figures 5.23 (a) through 5.23 (b) both show the average result s of the RCPT on the concrete samples that were subjected to ideal (moist) and heated curing conditions. Additionally, Figure 5.23 (a) represents the samples without heated aggregate while Figure 5.23 (b) shows the heated aggregate samples. Effect of Curing In Figures 5.23 (a) and 5.23 (b) moisture cured specimens showed a decrease in the chloride penetration for both the OPC and FA samples. At 28 days of age, both the OPC and FA moist cured samples initiated with moderate chloride penetration (2000 to 4000 coulombs) and by 90 days of age, both mixture types had decreased to low chloride penetration (1000 to 2000 coulombs). The heat cured specimen s did not always show a decreasing trend in chloride penetration. Typically, the OPC and FA samples under heated conditions had higher permeability readings from the 28 to 90 days of age in comparison to the water cured samples. By the 90 days of age, the coulombs ranged between 2870 6517 for the heat cured samples, thus the heated samples were classified as having moderate to high permeability. Effect of Cementitious Material When comparing the OPC to the FA samples in Figure 5.2 3 (a) and Figure 5.2 3 (b), the FA samples cured in water initially had higher permeability than the OPC samples. In Figure 5.23 (a) 28 day permeability for the water cured FA samples began to

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196 approach the permeability of the OPC samples. By 90 days of age, all water cured FA samples showed a lower permeability than the OPC water cured samples and fell within the classification of low permeability (See Figures 5.2 3 (a) and 5.2 3 (b)). Concrete containing fly ash subjected to heat curing generally had lower permeability than th e heat cured OPC samples at 28 day testing and remained lower than the OPC samples until the 90 day testing. However, all heat cured samples, whether the samples contained fly ash or not, exhibited a permeability that was either moderate or high. Effect of Aggregate Content Referring to Figures 5.2 3 (a) and 5.2 3 (b) for samples containing 55% or 65% coarse aggregate of total aggregate, there was negligible difference in permeability. The samples first measured moderate permeability at 28 days of age and eventually all resulted in low permeability. The heat cured samples showed a larger difference in performance among 55% and 65% coarse aggregate. However it was surprising that the permeability for the 65% coarse aggregate samples was lower than the 55% coarse aggregate samples when cured in heat. As discussed earlier it was expected with more aggregate there would be more heat storage thus affecting the distribution of the hydration products throughout the concrete sample and increasing the pores in the cementitious matrix. Effect of Heated Aggregate Overall there was little difference between concrete mixtures containing the no heated and heated aggregate. An outlier from Figure 5.2 3 (b) shows the OPC55H mixture with heated aggregate having at least a 50% higher permeability than its companion

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Figure 5.2 3 Average Rapid Chloride Ion Permeability Test Results ( a ) No Heated Aggregate, ( b ) Heated Aggregate (a) High Moderate Low Very L ow (b) 197

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198 mixture, OPC55H, from Figure 5.2 3 (a) without heated aggregate. In addition, there was the case where a heated aggregate mixture resulted in a lower permeability compared to the no heated aggregate mixture by 90 days of age (i.e. OPC55W). The majority of heated aggregate mixtures were ap proximately 10% higher than the companion mixtures with no heated aggregate. 5.5.4 Length Change Figure 5.2 4 shows the apparatus used to measure length change. Figures 5.2 5 through 5.2 6 show the percentage length change for the no heated and heated ag gregate samples respectively. Evening and morning changes were recorded due to the cyclic heating conditions created to represent diurnal temperatures for the day. Maximum temperatures were approximately 48 o C (118 o F) and minimum temperatures were about 2 2 o C (72 o F) to represent night temperatures. The lengths of the samples were measured in the morning before the heater turned on and in the evening after hours of exposure to maximum temperatures. Figure 5.2 4 Length Change Apparatus Comparing similar mixtures that experience different curing conditions shows that all heat cured concrete samples experienced more length change than the water cured samples. Most heat cured samples decreased in length. However, in Figure 5.2 5 (d) the

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199 50FA65H mixture did increase in length before 28 days and suddenly at 56 days. Maximum percentage length change for heat cured samples was about 0.06% for OPC samples and about 0.02% for FA samples in Figure 5. 2 5 In Figure 5.2 6 maximum percentage length change for heat cu red samples was about 0.08% for OPC samples and 0.04% for FA samples A comparison of the percentage length change in samples with different cementitious materials reveals that FA samples were usually 0.04% less than the OPC samples when heat cured. When w ater cured, the FA samples seem to have a slightly more linear expansion than the OPC samples (i.e. 50FA65W versus OPC65W in Figures 5.2 5 (d) and 5.2 5 (c) respectively and 50FA55W versus OPC55W in Figures 5.2 6 (b) and 5.2 6 (a) respectively). Aggregate content did not seem to affect FA samples as m uch as OPC samples. In Figure 5.2 5 the OPC samples differed by 0.03% while FA samples differed by 0.018% when comparing aggregate content. In Figure 5.2 6 OPC samples differed by 0.006% and FA samples differed by 0.002%. However, these differences did not necessarily always mean the 65% coarse aggregate mixtures had higher length change than the 55% coarse aggregate mixtures. The heated aggregate samples did have higher percentage length changes than the no heated samples. Maximum differences that occurred among the OPC samples were 0.04% and 0.028% for the FA samples as a result of heat curing. Overall FA samples appeared to have less of a change in length compared to OPC samples. These changes in leng ths in terms of units of length were not large. Maximum length change was about 0.02 cm (0.008 in).

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(a) (b) (c) (d) Figure 5.2 5 Length Change for No Heated Aggregate Samples 200

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(a) (b) (c) (d) Figure 5.2 6 Length Change for Heated Aggregate Samples 201

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202 5.6 Applying a Multiple Linear Regression Model to Determine the Significance of Testing Variables on HVFA Concrete versus OPC Concrete When Subjected t o Hot Weather Conditions 5. 6 .1 Background on Multiple Linear Regression Multiple linear regression models illustrate the relation between the dependent (response) variable and the independent (predictor) variables based on a regression equation (Hayter, 1996). The general form of the multiple regression equation with k variables is the following: y i 0 1 x i1 2 x i2 k x ik + e i i = 1,2,...,n (1) 0 is considered the intercept parameter and i is the parameter that determines how the input variable, x i has an influence on the response variable while all other input variables are fixed. 0 k is estimated using the method of least squares and are chosen so that the sum of the squares of the vertical distance between the actual obser vation and the fitted values is minimized. The null hypothesis is H 0 1 k =0 The alternative hypothesis is H A : i If i =0 then the input variable x i has no influence on the response variable and can be left out of the model. If the null hypothesis is rejected then x i has some influence on the response variable and should be included in the model. The hypotheses are compared to a t distribution such that the degrees of freedom are calculated from n k 1 (n = samples size, k+1= the number of parameters) A two sided p value (measure of plausibility) is calculated such that p value = 2 x P(X > t ) and X is a random variable with a t distribution with n k 1 degrees of freedom. A list of p values will be obtained that correspond to the parameters 0 k The p values are

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203 important for all parameters except 0 The input variables x i corresponding to the parameter i usually, should not be included in the model if the p value is larger than 10%. If the p value is smaller than 1% than the input variable is considered important to the model. If the p value is between 1% and 10% it is not obvious whether the input variable is important to the model and the decision to keep it is left up to the judgment (Hayter, 1996). 5.6.2 Application of the Multiple Linear Regression Models Compressive strength, permeability, and percentage length change were measured at common time intervals (28, 56, and 90 days). Ini tially each of the following conditions were expected to linearly affect the three measurements: (1) curing conditions, (2) aggregate content, (3) time of curing, and (4) temperature of aggregate. Therefore strength, permeability or percentage length cha nge is expected to be the result of the sum of the various conditions (each applying a certain level of influence). However, the degree of influence was unknown. The refore the goal of a multiple regression analysis for the study performed on the OPC and high volume fly ash concrete samples was to the determine the effects on the measured dependent variables ( X Y and Z ) as a result of a variety of experimental conditions and compositions or independent variables ( A B C D and T ) such that X = com pressive strength Y = permeability Z = length change as a percentage D ependent Variables

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204 A = cementitious material (cement vs. fly ash) B = curing condition (water vs. heat) C = aggregate content (55% vs. 65% coarse aggregate content of total aggregate) D= heated or not heated aggregate T =three common points in time (28, 56, and 90 days of curing) The three multiple linear regression models were designated as X = 0 1 A+ 2 B+ 3 C+ 4 D+ 5 T (2) Y = 0 1 A+ 2 B+ 3 C+ 4 D+ 5 T (3) Z = 0 1 A+ 2 B+ 3 C+ 4 D+ 5 T (4) Table 5.1 5 is a matrix showing the values gathered from testing compressive strength, permeability, and length change. The independent variables are either represented as a 1 or 0 to indicate t hat two cases (e.g cement or fly ash, heat or non heated aggregate) were tested within each independent variable. The independent variable T however, is identified as the actual number of days of curing (i.e. 28, 56, and 90). The independent variable ( T*B ) will be explained in a later section. Equations (2) through (4) were evaluated using the statistical package Minitab. Minitab results are shown in Appendix D. Figure D. 18 in the Appendix provides an explanation of the different parameters calculated within the regression analysis (these explanations are the bolded items in Figure D.1 8 ). The equations of the fitted curves for compressive strength, permeability and percent leng th change are shown in Table 5.16 Table 5.17 provides a summary of the results from Appendix D. The equations or Independent Variables

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205 response functions represent a hyperplane (a plane in more than t hree dimensions). Although it is difficult to picture the response fun ctions, the meaning of the parameters (coefficients) can be understood as follows: Referring to Equation (1), a unit increase in the indepen den t variable x k with all other independent variables held constant, means that the mean response E {y } will change based on the parameter k Table 5. 1 5 Matrix for Multi ple Linear Regression Analysis

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206 Table 5 16 Equations of Fitted Curves from 1 st Regression Analysis Table 5.17 Summary of 1 st Regression Analysis Dependent Variable Significant Variables Ins ignificant Variables R 2 Standard Deviation X 1 A, B, C D T 78.2% 540.204 psi (3.72 MPa) Y 1 B A, C, D, T 49.9 % 815.909 coulombs Z 1 A, B C, D, T 77.3 % 0.0125 % For compressive strength all p values were less than 10% except for the independent variable D This indicates that the variable D (aggregate was heated or not heated) is not needed in the model to improve the fit. All other p values that are below 10% indicate that the null hypothesis is not pl ausible and thus the strength has a relationship with the type of cementitious material ( A ), curing environment ( B ), coarse aggregate content ( C ), and number of curing days ( T ). The outputs for permeability (Refer to Figure D. 19 ) show that the variables C D and T are not significant within the model. This confirms the observational results discussed in the permeability section However, as noted from Figure 5.22 a and 5.22 b OPC55H (heated and no heated aggregate) samples were ou tliers, having differences in permeability up to 50% at 90 days of curing. The regression analysis for percentage length (Refer to Figure D. 20 ) change revealed that coarse aggregate content ( C ) and curing time ( T ) are not of statistica l significance w ithin the model. Again this confirms the observations made in the length change section However, from Figures 5.24 and 5.25 it can be seen that over time the percentage length change usually results as shrinkage for the samples cured in heated

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207 conditions, while the samples cured in water did not have such large changes in length over time. These differences may be a reason why the regression analysis showed that curing time ( T ) had no major effect on the samples length change. Within linear regression it is customary, upon reviewing the results of the initial regression analysis, to remove the variables that were not significant to each model and to perform the analysis again. However, the first analysis was completed assuming that th e predictors or the independent variables were additive. Therefore, it was within the interest of the author to run the same analysis with the inclusion of an interaction between the independent variables T and B This interaction term is also known as a bilinear term. It was assumed that the interaction would be important in developing a better model to fit the data for compressive strength, permeability, and percentage length change. The interaction was believed to exist because the level of change in the dependent variable is determined by the adjoining effect of T changing and B changing in the model. In other words, using strength as an example, it is expected that a sample should gain more strength with time but that strength should decrease by some factor if the sample was cured in heated conditions or the strength should increase if the sample was cured in water. The previous three multiple linear regression equations (2 through 4) changed to include the interaction term as follows. X = 0 1 A+ 2 B+ 3 C+ 4 D+ 5 6 TB (5) Y = 0 1 A+ 2 B+ 3 C+ 4 D+ 5 T + 6 TB (6) Z = 0 1 A+ 2 B+ 3 C+ 4 D+ 5 T+ 6 TB (7)

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208 Equations (5) through (7) were evaluated using the statistical package Minitab. Minitab results are shown in Appendix D as Figures D .21 through D. 23 Table 5. 1 8 shows the regression equations resulting from the second analysis and Table 5. 1 9 provides a s ummary of the results from Appendix D. A comparison of Table 5. 1 8 and 5. 1 9 shows how the interaction term changes the coefficients 0 2 and 5 Table 5.18 E quations of Fitted Curves from 2 nd Regression Analysis Regression Analysis X Y, and Z versus A, B, C, D, T, T*B X 2 = 6042 1777 A 663 B+468 C 157 D+15.5 T 18.0T*B Y 2 = 4032 467 A 529 B 377 C+86 D 22.1 T+32.7T*B Z 2 = 0.00160+0.0181 A 0.0239 B+0.00070 C 0.00649 D+0.000030 T 0.000251 T*B Table 5 19 Summary of Regression Analysis When Including the TB Interaction Term Dependent Variable Significant Variables Ins ignificant Variables R 2 Standard Deviation X A, B, C, T, TB D 82.6% 488.115 psi (3.36 MPa) Y A, B, T, TB C, D 64.6% 693.672 coulombs Z A, B C, D, T, TB 79% 0.0122 % The effects of the coefficients and the fit that they provide to the model can be examined by looking at just the ( 5 T+ 6 TB ) term from equations (5) through (7). Assuming all other independent variables are constant and comparing the response variable (dependent variable) with the predictor (independent variable) T the following should be expected with the ( 5 T+ 6 TB ) term: Compressive strength X 5 T+ 6 TB is (15.5 18.0B)*T from X 2 in Table 5. 17 If B = 0 (water cured), then the slope of the term is 15.5, which means strength should increase as time increases. If B= 1 (heat cured), then the slope of the term is 2.5 which means strength should decrease as time increases.

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209 To provide confirmation of the two different slopes the average strengths resulting from the regression equation X 2 are graphed against the average of the real measured strengths from Table 5. 15 when B=0 and B=1 at T = 28, 56, and 90 days. This graph is shown in Figure 5. 2 7 Figure 5.27 Effects of the Interaction of T and B on Compressive Strength Permeability Y 5 T+ 6 TB is ( 22.1+32.7B)*T from Y 2 in Table 5. 17 If B = 0 (water cured), then the slope of the term is 22.1, which means permeability should decrease as time increases. If B= 1 (heat cured), then the slope of the term is 10.6, which means permeability should decrease as time increases. To provide confirmation of t he two different slopes the average permeability values resulting from the regression equation Y 2 are graphed against the average of the real measured permeability values from Table 5.1 5 when B=0 and B=1 at T = 28, 56, and 90 days. This graph is shown i n Figure 5.2 8

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210 Figure 5.2 8 Effects of the Interaction of T and B on Permeability Percentage Length Change Z 5 T+ 6 TB is (0.000030 0.000251B)*T from Y 2 in Table 5.17 If B = 0 (water cured), then the slope of the term is 0.000030, which means percentage length change should increase as time increases. If B= 1 (heat cured), then the slope of the term is 0.000221, which means permeability should decrease as time increases. To provide confirmation of the two different slopes the average perc entage length change resulting from the regression equation Z 2 are graphed against the average of the real measured percentage length change values from Table 5.1 5 when B=0 and B=1 at T = 28, 56, and 90 days. This graph is shown in Figure 5. 2 9 The interaction of A and B was also considered but the R 2 values for the models did not increase as much as they did with the interaction between T and B except for the model for permeability ( Z ). Nevertheless, the decision was made that the T and B inte raction was the only interaction that would be used to develop regression models. The influence of A (descriptor cement or fly ash) on all regression analyses, however,

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211 was significant in all models. Thus this provides evidence that compressive strength, permeability, and percentage length change will vary with use of cement or fly ash. Figure 5. 2 9 Effects of the Interaction of T and B on Percent Length Change 5.6.3 Revision of Multiple Linear Regression Analysis with Original Data Previously, the multiple linear regression model was developed with the average values. For example, for each testing day the compressive strength (28, 56, and 90 day testing) was the result of at least two samples averaged and a linear regression equatio n was fitted to these average values. However, using solely the averages of the data did not take into account the variability within each testing day. Therefore the multiple linear regression analysis was carried through with the inclusion of all origin al data. Below is a discussion of the resulting coefficient of determination (R 2 ) and standard deviation of each of the multiple linear regression equations.

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212 Compressive Strength The first regression analysis is not included in this comparison becaus e it did not include the interaction terms T*B. X 2 represents the regression analysis with the averages and X 3 is the regression equation which resulted from all original data. The influence of each of the input variables (A through TB) changed. This is apparent when comparing the coefficients in each of the equations in Table 5.20 Table 5.20 A Comparison of E quations of Fitted Curves From 2 nd and 3rd Regression Analysis for Compressive Strength Regression Analysis X Y, and Z versus A, B, C, D T, T*B X 2 = 6042 1777 A+663 B+468 C 157 D+15.5 T 18.0T*B X 3 = 6014 1802 A+804 B+452 C 157 D+15.3 T 18.4T*B In Table 5.21 the variables that are significant are shown. The variables were considered significant if the p values were less than 0.05. Both analyses resulted in the same variables being significant. The coefficient of determination (R 2 ), however, decreased. So with the inclusion of original values the analysis revealed that the spread of the compressive strength data made it a little more complex to fit a curve to the data. However, with more variability in the data, this resulted in a larger standard deviation for estimating a linear regression equation. With the new standard deviation, at least a little more than 2/3 of the original data (approximately 69%) falls within one standard deviation. Table 5.21 Comparing Significant V ariables, R 2 and Standard Deviations for Compressive Strength Dependent Variable Significant Variables Ins ignificant Variables R 2 Standard Deviation X 2 A, B, C, T, TB D 82.6% 488.115 psi (3.36 MPa) X 3 A, B, C, T, TB D 76.9% 554.557 psi (3.82 MPa)

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213 Note regarding the standard deviation in the multiple linear regression analysi s : The linear regression analysis calculates a standard deviation for all compressive strength values including all results for HVFA and OPC together. As was seen in the compressive strength results in Figure 5.19 the differences in strength between OPC and HVFA are taken into account with the standard deviation calculated b y the multiple linear regression. In other words the standard deviation is representing the sprea d of the strength results between HVFA and OPC. This is also true for all standard deviations reported for permeability and length change. Permeability In Table 5.22 the multiple linear regression equations for permeability did not change despite including twice the set of data that was included in the first analysis. However, in Table 5.23 it is clear that R 2 decreases and standard deviation increases. With the new standard deviation approximately 76% of the data falls within one standard deviation of the multiple linear regression analysis. Table 5.22 A Comparison of E quations o f Fitted Curves From 2 nd and 3rd Regression Analysis for Permeability Regressio n Analysis X Y, and Z versus A, B, C, D, T, T*B Y 2 = 4032 467 A 529 B 377 C+86 D 22.1 T+32.7T*B Y 3 = 4032 467A 529 B 377 C+86 D 22.1 T+32.7 T*B Table 5.23 Comparing Significant Variables, R 2 a nd Standard Deviations for Permeability Dependent Variable Significant Variables Ins ignificant Variables R 2 Standard Deviation Y 2 A, C, T, TB B, D 64.6% 693.672 coulombs Y 3 A, C, T, TB B, D 54.4% 823.454 coulombs Length Change In Table 5 .24 the multiple linear regression equations for length change show how the fitted equations did not change because the amount of data for length change did not

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214 increase. The number of samples per mixture remained at 1 per mixture Thus in Table 5.25 the R 2 and standard deviations remained the same as well. This meant that 73% of the original data fell within one standard deviation of the estimated data. Table 5.24 A Comparison of E quations o f Fitted Curves f rom 2 nd and 3rd Regression Analysis for Length Change Regression Analysis X Y, and Z versus A, B, C, D, T, T*B Z 2 = 0.00160+0.0181 A 0.0239 B+0.00070 C 0.00649 D+0.000030 T 0.000251 T*B Z 3 = 0.00160+0.0181 A 0.0239 B+0.00070 C 0.00649 D+0.000030 T 0.000251 T*B Table 5.25 Comparing Significant Variables, R 2 a nd Standard Deviations for Permeability Dependent Variable Significant Variables Ins ignificant Variables R 2 Standard Deviation Z 2 A, B C, D, T, TB 79% 0.0122 % Z 3 A, B C, D, T, TB 79% 0.0122 % Checking the Validity of the Model The question to consider is the following: Is there at least one independent variable linearly related to the dependent variable? To answer this question the following hypothesis can be tested: H 0 1 2 k = 0 H 1 i is not equal to zero i is not equal to zero, the model has some validity. The hypothesis is tested using the method of Analysis of Variance (ANOVA). The analysis of variance was completed for the results of the multiple linear regressio n analysis using Minitab. A F statistic was calculated for each linear regression analysis by dividing the mean squares by the mean squares error. The p value was also determined. As such either the F statistic or the p value can be used to reject or ac cept the null hypothesis H 0 The F statistic and p value are shown in Table 5.26 for the linear regression analysis for

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215 strength, permeability and length change. If the p values shown in Table 5.26 are ce interval) it is obvious that the p values are much smaller than 0.05. Thus, this also represents a large F statistic and if F is large the multiple linear regression model is considered valued for each response variable (strength, permeability, and len gth change). The null hypothesis is rejected and i is not equal to zero and at least one independent variable (cementitious material, curing condition, heated aggregate, aggregate content, days of curing) is linearly related to compre ssive strength, permeability, and length change. Table 5.26 Summary o f F Statistic a nd P Value f rom ANOVA Summary Overall the results of including all original data allowed for the coefficients in the multiple linear regressions to not change by much or not change at all. However, small changes in the R 2 and standard deviation showed how the fitted curves did not allow for all the original data to be accurately represented. Nevertheless, at least 2/3 of the compressive strength, permeability, and length change data remained in at least one standard deviation of the estimated data. Finally the multiple linear regression was model was validated using ANOVA and revealed that at least one of the independent variables is linearly related to the response variable. 5.7 Summary of Strength, Permeability, Length Change, and Multiple Linear Regression. Although high temperatures have been addressed for making, placing, and curing concrete the subject of a high temperature environments along with effects of heated Compressive Strength Permeability Length Change F = 62.17 F = 17.73 F = 25.64 p = 0.000 p = 0.000 p = 0.000

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216 aggregate and amount of aggregate is not well addressed in research. This dissertation pres ent ed evidence that fly ash can be beneficial to concrete for maintaining lower internal concrete temperatures, however when you have combined effects such as heated aggregate, and varying aggregate content and curing in hot weather conditions then strengt h results revealed that OPC will still perform better than HVFA concrete mixtures (based on the particular mixture design used in this dissertation) Nevertheless, HVFA and OPC concrete mixtures remained above design strength for the 90 days of curing. Fo r permeability OPC and HVFA mixtures showed decreases in permeability if water cured I f heat cured the permeability reach ed moderate permeability. For heat cured OP C mixtures permeability fell in to the high permeabilit y range. The percentage length c hange in wa ter cured samples was very close to zero. HVFA heat cured samples did exhibit some shrinkage but about 0.02% less than OPC heat cured samples. Overall HVFA concrete samples performed better or similarly to OPC concrete in terms of length chang e. From the multiple linear regression analyses the goal was to determine if cementitious material, aggregate content, aggregate temperature, heat curing, and curing days ( these are considered independent variable s ) were statistically significant towa rds the results of strength, permeability, and length change. P values were calculated for each independent variable and they were compared to independent variables proved to be significant for the dependent variables measur ed. Strength, for example, was significantly affected from the variables cementitious material used, curing condition s used, aggregate content, and number of curing days. Heated or no heated aggregate did not have much of an effect on either of the mixtu res for strength,

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217 permeability, and length change. It can be concluded that HVFA should be considered for extreme hot weather conditions but results also revealed that OPC concrete can be just as beneficial in these conditions.

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218 6. Conclusions and Recommendations 6.1 Conclusions With the production and use of concrete green house gases (GHG) are released into the atmosphere. GHGs have been connected with the onset of climate change events. The events could lead to varying rain events that lead to flooding, and extreme high temperatures that can affect the performance of concrete infrastructure today. H owever, with concrete need to research if attributes of concrete technologies can contribute to carbon mitigation and climate adaptation. The purpose of this dissertation was to evaluate Pervious and structural and environmental properties that could contribute to carbon mitigation and climate adaptation in cities with Rajkot as a case study. 6.1.1 Carbon Mitigation: An MFA LCA Approach The CMA reports a cement emissi on factor (0.83 tonnes CO 2 /tonne cement) very close to the calculations performed in this disseration for the state of Gujarat (0.84 tonnes CO 2 /tonne cement). However, it was necessary to perform the cement life cycle inventory because there are other con tradicting sources reporting a range of emission factors for Indian cement (0.6 to 1.0 tonnes CO 2 /tonne cement). Actually this range is represenative of the how large companies and small companies generate a majority of the electricity on site. However, the efficiency of production for the smaller companies is less than that of the larger companies which seems to make the emission factors fluctuate. Other materials and transportation needed for concrete revealed that much of the emissions is arising fro m cement manufacturing. An MFA LCA of cement in Rajkot

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219 revealed per capita cement use in Rajkot is 0.15 tonnes/person more than Delhi but is still 0.11 tonnes/person below that of a U.S. city like Denver. Final MFA LCA calculations for pervious concrete and HVFA concrete mixtures showed at most a 21% and 47% reduction in emissions, respectively, compared to a conventional concrete used in Rajkot. 6.1.2. Climate Adaptation: Pervious Concrete The purpose of this study was to determine environmental and structural properties of a pervious concrete demonstratio n in Rajkot, India Changes in rain events can become an issue for stormwater solutions F lood ing are a concern for water quality, capacity and long term durability of stormwater designs. The pervious concrete demonstration revealed that Rajkot material s were acceptable for making a pervious concrete mixture that provided adequate p orosity and hydraulic. The typical porosity of 15 to 25% and hydraulic conductivity above the impervious zone of approximately 0.15 cm/s (0.06 in/s) were met. The pervious c oncrete also showed the water filtering capabilities and potential for reducing some polluting parameters such as nitrogen levels. present in concrete. Pervious concrete stren gth reached at least 6.9 MPa (1000 psi) which could be satisfactory for landscaping infrastructure. However, the long term performance of strength was determined uncertain (on average). Cubes only met design strength of 13.8 MPa (2000 psi) once out of 4 batches; cylinders met design strength once out of 3 batches A strength relationship was deemed necessary for cross country com parisons of strength since it is unclear which shape is more appropriate for representing strength for pervious concrete H owe ver, due to the large spread in strength results [standard

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220 deviations between 2.6 MPa (377 psi) and 3.8 MPa (561 psi)] in both cylinders and cubes a relationship was not determined at this time. 6.1.3 Climate Adaptation: HVFA Concrete Although high te mperatures have been addressed for making, placing, and curing concrete the subject of a high temperature environments along with effects of heated aggregate and amount of aggregate is not well addressed in research. This dissertation presented evidence t hat fly ash can be beneficial to concrete for maintaining lower internal concrete tempera tures. The research also showed that when you have combined effects such as high temperatures, heated aggregate, and varying aggregate content and curing in hot weath er conditions compressive strength results for ordinary portland cement ( OPC ) concrete mixtures will still perform better than high volume fly ash ( HVFA ) concrete mixtures designed for this study Nevertheless, HVFA and OPC concrete mixtures remained above design strength for the 90 d ays of curing in extreme temperatures above 37.8 o C (100 o F) For permeability, on average OPC and HVFA mixtures showed decreases in permeability over time If water cured both OPC and HVFA concrete mixtures demonstrate Low Permeability (1000 to 2000 coulombs). However if heat cured HVFA showed slightly less permeability than OPC mixtures, demonstrating Moderate Permeability (2000 to 4000 coulombs) by 90 days. For heat cured OPC mixtures permeability fell in to the high pe rmeability range (above 4000 coulombs) The percentage length change in water cured samples was very close to zero. HVFA heat cured samples did exhibit some shrinkage but about 0.02% less than OPC heat cured samples Overall, length change measurements showed that HVFA concrete were about 50% lower than OPC concrete when heat cured.

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221 Based on all tests results it was difficult to conclude whether HVFA concrete performed better than OPC concrete in terms of strength and durability. It was concluded, ho wever, that these HVFA and OPC concrete mixtures could both be adjusted based on the (independent variables) cementitious material used, curing condition s used, aggregate content, and number of curing days allowed for the concrete A multiple linear regre ssion analysis was performed to model compressive strength, permeability, and length change (dependent variables) in order to determine which independent variables had a significant influence on the concrete mixtures adaptability to hot weather conditions. The multiple linear regression analysis showed that n ot all independent variables proved to be significant for the dependent variables measured. Strength, for example, was significantly affected from the variables cementitious material used, curing cond ition s used, aggregate content, and number of curing days. Heated or no heated aggregate di d not have much of an effect on either of the mixtures for strength, permeability, and length change. It can be concluded that HVFA should be considered for extrem e hot weather conditions but results also revealed that OPC concrete can be just as beneficial in these conditions. 6.2 Contributions This study provided the following contributions to literature: It was the first study to perform an MFA LCA on site mi xed concrete specifically for India It was the first study that provided a demonstration of pervious concrete to a city in Gujarat, India

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222 It was one of the first studies to provide a compressive strength a relationship between pervious concrete cube and cy linders when the mixture design involved a comparison of concrete materials. It was one of the first studies to have a combination of heated aggregate, heat curing, cyclic temperatures, different aggrega te content and long term curing in order to measure conditions. One of few studies with multiple linear regression for variable significance on HVFA and OPC in hot weather This study has also provided the following contributions directed towards prac titioners: Provide d an MFA LCA based tool for determining environmental impact of different on site concrete mixed mixtures Introduced the method and benefits of a pervious concrete system and suggested future use of system Provided verification that two sources of Indian fly ash hav e beneficial properties towards achieving a concrete strength of 27.6 MPa (4000 psi) which is important to pavement and certain structural designs. Provided verification that HVFA can perform a bove design strength in semi arid to arid conditions and improve permeability and mitigate length change 6.3 Recommendations and Future Research Based on the work described in this study many recommendations can be made t o help improve the results. For e xample emissions estimates from cement and on site concrete production can be represented by CO 2 equivalents, the standard deviation of the

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223 pervious concrete can be reduced through an increase in sample size and improvements made in the curing process, and sample size of the HVFA concrete tests can be increased by establishing a control and best performing concrete mixture in strength and durability separately. 6.3.1 MFA LCA Recommendations It was stated in Chapter 3 that other greenhouse gas emissions b esides CO 2 were not included due to unavailability of the data. CO 2 equivalents can be estimated for India through use of nitrous oxide and methane data available from U.S. cement and concrete (200 7) study included emissions from the use of water for mixing concrete. However, it was not clear whether all cities in India manually dig for water or use equipment for attaining water. A water emissions factor should be determined if necessary. Emissio ns were estimated for on site mixed concrete, which is the dominant type of concrete used in concrete construction in India. However, ready mixed concrete operations are progressively increasing in India. Emissions from Indian ready mixed concrete are be neficial to estimate. Lastly, more research is recommended for determining the efficiency of captive power plants. 6. 3 2 Pervious Concrete Recommendations Image Analysis Orientation of aggregate and actual cross sectional area of the pervious concrete surface can vary throughout the depth of a pervious concrete sample. Orientation of the aggregate can affect the mechanical properties of the pervious concrete such as compr essive strength. In a study by Mahoub, Canler, Rathbone, Robl, and Davis (2009) a pervious concrete slab was tested for various properties. In particular the authors had

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224 sliced the slab samples into various layers and identified the orientation of the ag gregate. Observations proved the orientation was very different throughout the layers and these observations were identified as being important for protocols that help approximate field conditions of pervious concrete. Image analysis was recommended in t his study as well. Identifying particle orientation in the future could be used to determine actual permeability (hydraulic conductivity). Weibull Statics Weibull statistics might be useful in determining specimen size effects on the compressive str ength performance between a cylinder and a cube. For example, w ithin a small sample or rather a small volume (i.e. cylinder with 100.5 in 3 ) composite there is a finite probability that there will be a flaw sufficiently large enough to cause failure at a p articular stress level. On a specimen made up of a large number of small volume elements (i.e. cube with 216 in 3 ) the probability of the existence of a serious flaw is much larger. Large specimens are therefore inherently weaker, and so will have lower ult imate strengths and give lower fatigue lives. Weibull statistics can be used to express survival probability in terms of specimen volume and stress or fatigue life. Weibull statistics, however, contradicts the information reported in Mindess, Young, and D arwin (2003) and Neville (1973) that suggests you most often get higher strengths with cubes. But another interpretation of Weibull statistics suggests that cylinders and cubes (100 .5 in 3 and 216 in 3 respectively) do not sufficiently differ in volume as indicated by Weibull statistics (A large volume = a large number of smaller volume elements). More research into weibull statistics applicability to cylinders and cubes should be performed.

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225 6.3.3 HVFA Concrete Recommendations Phase IV Redesign for testing HVFA concrete in hot weather conditions The literature on concrete in urban areas exposed to hot weather conditions revealed that even in recent weather conditions concrete pavements tend to experience deterioration and detr imental effects due to hot weather. In 2012 several concrete pavements had buckled as a result of consecutive temperatures remaining above 32.2 o C (90 o F). Additionally literature suggested that not many studies have attempted to test concrete under a comb ination of hot weather conditions and adjust the mixture design to counteract the effect of the hot weather conditions. Therefore, in this research the hot weather conditions included curing concrete specimens under diurnal temperatures between 22.2 o C (72 o F) and above 37.8 o C (100 o F) and heating the aggregate to about 65 o C (149 o F) just before including them in the mixture, to represent the aggregate being exposed to hot weather. To offset the effects of the hot weather, 50% fly ash (to replace cement) and varying the coarse aggregate content (of total aggregate) were used simult aneously in the mixtures. Fly ash is known to lower the internal heat during hydration and generally a higher use of coarse aggregate helps to reduce drying shrinkage problems. This information was discussed earlier in the chapter. The HVFA concrete m ixtures were compared to OPC mixtures in terms of compressive strength, permeability, and length change during 90 days of curing (the recommendation for fly ash concrete is at least 56 days of curing). As discussed in the summary, the results revealed tha t overall OPC concrete had higher compressive strength throughout the duration of the testing. However, the HVFA concrete sample strengths remained above the design strength. The OPC concrete and the HVFA concrete samples

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226 appeared to perform either simil arly or the HVFA concrete performed slightly better than OPC concrete samples according to the results for permeability and length change. However, based on the limited amount of samples that were designated for the testing of compressive strength, pe rmeability and length change a definitive conclusion could not be made between HVFA and OPC concrete under hot weather conditions. Even if the multiple linear regression analysis included all data without taking averages the standard deviation of the mult iple linear regression equations, for example, did not encompass all variations in strength that was recorded during this study. Thus it is recommended by the author that the following testing plan be used to verify the performance of high volume fly ash concrete under a combination of hot weather conditions. Design of Experiment The experiment will involve two phases of testing. Phase I will be concerned with mostly later age concrete properties and results will be applied towards improving the result s for multiple linear regression. Phase II will be focused on early age concrete properties and the results will be applied towards elastic potential energy, temperature profiles, and changes in strength. The course of testing will take approximately two years since 90 days of testing are needed for total curing time. Mixture designs will remain the same as listed in Table 5. 1 1 however, the worst case scenario of hot weather conditions will be tested first. The order of testing will commence with two m ain mixtures 50% FA and OPC with 65% coarse aggregate content. Table 6.1 summarizes the order in which the mixtures will be tested. The base mixture design is shown in Table 6.2 which briefly mentions the cement, total aggregate content, water/cementitio us ratio and the fly ash

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227 replacement of the ordinary portland cement when required for the mixture. A water reducing admixture will be used as well and will be applied using the same dosage described in Table 5.11. Table 6.1 Order of Performing Mixtur es Table 6.2 Base Mixture Design W/C+FA 0.4 FA replacement (%) 50 Design Compressive Strength 27.6 MPa (4000 psi) Total Cementitious Content (kg/m 3 ) 376.7 Approximate Total Aggregate (kg/m 3 ) 1800 1 kg/m 3 = 1.68554 lb/yd 3 Phase I testing is summarized in Table 6.3 Phase II testing is summarized in Table 6.4 Figure 6.1 shows a sample of what the testing schedule could look like for Phase I through Phase II. Both water and heat curing setup of equipment and tanks will remain

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228 the same as was used in this dissertation. However, a humidity sensor is recommended for the he at curing tank. The humidity sensor can be connected to the datalogger. Table 6.3 Phase I Testing Summary for Each Mixture Table 6.4 Phase II Testing Summary for Each Mixture Figure 6.1 Sample Schedule for Competing Phase I II Testing Phase I Testing: Improving Multiple Linear Regression Analysis In the multiple linear regression analyses the results suggested that heated aggregate may not be of statistical significance and have no influence on the strength, permeability, and length change res ults. Nevertheless, since not enough samples were

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229 used to make this conclusion the condition of using heated aggregate in the mixture is still recommended for the testing described in this section. Later age testing results are preferred for the multip le linear regression analysis for a couple of reasons. (1) Strength testing for both the HVFA and OPC concrete begin to reach a stable gain in strength by 28 days of curing. Before 28 days the rate of strength gain constantly changes (especially between 0 and 7 days of strength) as can be seen in Figures 5.17a and 5.17b. Therefore, it is expected the major changes in strength gain should be mainly be influenced by the curing conditions and if there were heated aggregate in the mixtures as is seen in Figur es 5.18a and 5.18b, (2) Permeability testing is more commonly tested at or after 28 days of curing. The samples tested in Phase I will be included with the results that were recorded during the completion of this dissertation thus increasing the number of samples for the multiple linear regression analysis. After combining the sample results between this dissertation and Phase I then compressive strength will have a total of at least 8 samples per day, permeability will have 4 samples per day, and leng th change will have 4 samples per day for each mixture. Phase II Testing: Early age data to model length change and relate thermal evolution effects to fracture patterns. Phase II testing will aim towards collecting more data regarding length change, modulus of elasticity, and internal temperatures of the concrete while curing. In addition to length change being useful in the multiple linear regression analysis, length change measurements will be beneficial towards developing a finite element model of a pavement slab that is exposed to hot weather conditions. The ultimate goal of the finite

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230 element model would be to simulate buckling of the pavement slab. The modulus of elasticity will be used to determine the potential energy that can devel op in heat and water cured concrete samples when subjected to compressive loading. Measuring internal temperatures will be useful in confirming whether HVFA concrete can maintain at least lower temperatures than the OPC concrete. Lower concrete temperatu res can reduce thermal stresses, drying shrinkage cracking, and permeability, and help preserve long term concrete strengths. In the next few paragraphs the method of either using the data or taking measurements for length change, modulus of elasticity, a nd internal temperatures will be discussed further. Length Change Modeling The factors that contribute to cracking and failure of early age concrete may be due to temperature, creep, and shrinkage. Creep is a deformation that occurs in the concrete ove r time and is dependent on the loading imposed on the concrete. Whether the concrete is loaded or not, shrinkage results from the chemical and physical changes during the hydration process and will be affected by the surrounding environment. The occurren ce of creep and shrinkage can be linked to buckling. As part of this phase of testing it is implied that knowing the length change of concrete exposed to hot weather conditions over time will be useful in constructing a finite element model. The idea is to model a concrete pavement slab built up of rectangular shapes similar in size to those beams tested in lab for length change. Figure 6.2 shows a simple example of what the finite element mesh would look like.

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231 Figure 6.2 Example of Finite Element Mesh a nd a Close Up of a Single Element Based o n Dimensions of the Length Change Beam Made i n Lab Modulus of Elasticity and Potential Energy Early age (1 14 days of curing) strength tests and modulus of elasticity tests were originally conducted in the research. The early age strength test showed how heat cured concrete (including those samples with heated aggregate) gained strength at a sligh tly higher rate than water (ideally) cured concrete (Refer to Figures 5.17 and 5.19). Within this dissertation the early age modulus of elasticity data was only used to recognize the d on modulus of elasticity was also going to be used to determine the potential energy stored in heat cured concrete versus water cured concrete while under compressive loading. Under Phase II testing the determination of the elastic potential energy from compressive loads will be explored further. The elastic potential energy became of interest for this research because a comparison between HVFA and OPC concrete, when testing for compressive strength, revealed different failures. For example, heat cured OPC concrete samples tend to break or fracture explosively versus and the subtle or softer failures that the heat cured HVFA concrete demonstrated. Elastic potential energy is the work done to deform object being loaded but can return to its original sha pe if the loading is released. Elastic potential energy can be studied rather than fracture energy because during testing of modulus of

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232 elasticity we can determine the energy stored in the sample from a stress versus strain graph. Figure 6.3 demonstrates how the stress of an OPC water and heat cured sample are plotted against the strain of the concrete samples. The area under the approximate straight lines represents the elastic potential energy. The difference in energy is the shaded area shown in Figu re 6.3 In this case it appears that more energy is stored in a water cured sample versus a heat cured sample of OPC concrete, therefore, failure in the water cured sample might be assumed to be more pronounced than the heat cured sample. Figure 6 .3 Difference between Elastic Potential Energy of Water Cured and Heat Cured OPC Concrete Sample after 90 Days of Curing Internal Temperatures Early age data is especially important when measuring the internal temperature of the concrete as it is curing As was seen in Figures 5.10 and 5.11 the temperature profiles showed that HVFA concrete can successfully maintain the internal temperatures of the

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233 concrete at about 5% to 11% lower than OPC concrete internal temperatures (depending on the temperature of the surrounding environment). This difference in temperature is best measured during the first 3 days of curing when the exothermic reaction occurs during the hydration process. Having a lower internal temperature during hydration can be beneficial towa rds concrete cured in hot weather conditions. Lower internal temperatures of concrete can possibly help moderate evaporation and thermal cracking during the curing process. Originally, during this study, temperatures were being recorded for each mixture throughout the curing process; however, the thermocouples placed within the concrete would sometimes be damaged and stop recording temperatures. It was not clear if the damage occurring was due to a reaction between the thermocouple wires and the cement p aste or if the wires were being crushed by the hardening of the cement paste. Another method, compared to the one used in this dissertation is being recommended. Alternative Method Instead of using a liquid tape to protect the ends of the twisted wires an epoxy will be used that can harden to about a 6.35 mm (1/4 inch) thick once dried. The epoxy can be purchased from any hardware store. Additionally thicker thermocouple wires shou ld be used as well. The diameter of the wire used in this dissertation was a AWG 24. The same Type J thermocouple wire with a diameter of AWG 20 shall be used instead. The placement of the wire will be similar to that described in the dissertation. Thus the thermocouple wire is placed inside the cylinder mold, half way the length of the cylinder mold while attached to a

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234 wood dowel. Figure 6.4 provides a schematic showing the placement of the dowel and thermocouple in the concrete cylinder. Figure 6.4 Schematic of Placement of the Thermocouple in Concrete C ylinder Summary of Experimental Plan An experimental plan has been outlined for quantifying the effects of hot weather conditions (heat curing in diurnal temperatures, and heated aggregate) an d is compared to the effects of ideal water curing. The mechanical properties (compressive strength, length change and permeability) of HVFA and OPC concrete, while being exposed to the hot weather conditions, would be compared. The curing conditions are intended to simulate changes in the climate that cause temperatures to remain above 37.8 o C (100 o F) for long periods of time. This experimental outline is a result of the outcomes of this dissertation. The outcomes revealed that although HVFA concrete ha d lower strengths than the OPC concrete samples the HVFA never fell below design strength and HVFA had comparable or slightly better resistance to permeability and length change compared to the OPC concrete samples. However, as part of this dissertation t he results are only preliminary and cannot be used to make definite conclusions until supported with more data. Thus this experimental outline presents two major goals through two phases of

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235 testing. Phase I is meant to accomplish increasing the number of samples to replicate the results presented in this dissertation. Phase I and II testing together have the purpose of extending the use of the data in models. The length change is intended to be modeled as shrinkage experienced by pavements exposed to ho t weather conditions, applying compressive strength will have the purpose of quantifying differences in stored energy by HVFA and OPC concrete which should lead to an understanding of the how either of the concrete mixtures could fail while in service. An d finally, modeling of the temperature profile can be used to verify lower curing temperatures for HVFA concrete compared to OPC concrete while placed in hot weather conditions. 6.4 Final Remarks Regarding Sustainability This study was developed as part of the advancement of interdisciplinary research and sustainability. In order to have completed this study it involved the comprehension of other disciplines, culture, social behavior that allowed for collaboration with other individuals and organizations that are directly involved with the development of infrastructure. It is the hope of the author that the audience developed the understanding that although emissions and other impacts on the environment are most likely arising from the use of material s, energy, equipment, etc. society is still highly dependent on each of these things. The goal of this dissertation was meant to improve upon the current knowledge of materials that we use on a daily basis, such as concrete so as to find ways to reduce impacts on society and the environment with current infrastructure technology

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244 Denver, United States -Colorado. Retrieved January 26, 2011, from Dissertations & Theses @ University of Colorado System. (Publication No. AAT 3273499). Schindler, A. K. (2004). Effect of Temperature on Hydration of Cementitious Mat erials. ACI Materials Journal, 101 (1), 72 81 Schumacher, K., Sathaye, J. (1999). efficiency, and carbon emissions (Environmental Energy Technologies Division LBNL 41842) Berkeley, CA: Ernest Orlando Lawrence Berkeley National Laboratory Senthil, S., and Santhakumar, A. R. (2005). Quantification of temperature rise during hot weather concreting, Proceedings of the 6 th International Congress Conference on Global Construction: Ultimate Concrete Opportunities University of Dundee, Scotland, 59 66. Shukla, P. R., Biswas, D., Nag, T., Yajnik, A., Heller, T., & Victor, D. G. (2004). Captive Power Plants:Case Study of Gujarat India. A working paper from the Program on Energy and Sustain able Development at the Center for Environmental Science and Policy. Retrieved 2012 from the website http://cesp.stanford.edu/pesd Sidhee Cement. (2011). 37 th Annual Report 2010 11 Retrieved in 2012 from http://www.hathi sidheecements.com/sidhee_site/index.html Siemens, GlobeScan, MRC McLean Hazel. ( 2007). Megacity challenges: a stakeholder perspective Munich: Seimens AG Retrieved 2012 fr om http://www.siemens.com/entry/cc/features/urbanization_development/all/en/pdf/study_m egacities_en.pdf Sisavath, S., Jing, X., and Zimmerma n, R. W. (2001). Laminar Flow Through Irregrularly Shaped Pores in Sedimentary Rocks. Transport in Porous Media, 45 41 62 Solis, A. V., Durham S. A., Rens, K. L., & Ramaswami, A. (2010). Sustainable concr ete for the urban environment: A proposal to increase fly ash use in concrete, Proceedings of the ASCE Green Streets and Highways 2010 Conference : An Interactive Conference on the State of the Art and How to Achieve Sustainable Outcomes 389 (33 ), 401 407 doi: 10.1061/41148(389)33 Soli s, A. V., Durham S. A., & Ramaswami, A. (2012). Providing Stormwater Management Solutions in Rajkot India: A Pervious Concrete System Demonstration. The International Journal of the Constructed Environment 2 (3), 135 154. Tarr, J. A. (1984). The evolut ion of the urban infrastructure in the nineteenth and twentieth centuries, In R. Hanson (Ed.), Perspectives on urban infrastructure (pp. 4 66). Washington, D.C.: National Academy Press.

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245 Tennis, P. D., Leming, M. L., & Akers, D. J. (2004). Pervious Concret e Pavements Skokie, Illinois: Portland Cement Association. The Indian Concrete Journal (2004). Can HVFAC technology be adopted for site mixed concrete? Ultra Tech. (2012). Milestones Retreived from http://www.ultratechcement.com/milestones.php UltraTech Cement Limited. (2011). UltraTech Cement Limited Annual Report 2009 2010 Retrieved in 2012 from http://www.ultratechcement.com/ United Nations (UN). (2007). World Urbanization Prospects The 2007 Revision Highlights Retrieved from http://www.un.org/esa/population/publications/wup2007/2007WUP_Highlights_web.pdf United Nations. (2009). World Urbanization Prospects The 2009 Revision Highlights Retrieved from http://esa.un.org/unpd/wup/Documents/WUP2009_Highlights_Final.pdf United Nations. (2010). UN 2010 among the deadliest years for disasters, urges better preparedness. Retrieved from http://www.un.org/apps/news/story.asp?NewsID=37357&Cr=disaster+reduction&Cr1 United Nations. (2010). Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat. World Popu lation Prospects: The 2010 Revision Retrieved from http://esa.un.org/unpd/wpp/index.htm U.S. Department of Energy (2003). Energy and emission reduction opportunities for the cement industry Prepared by Choate, W. T. Columbia, MD: BCS Inc. U.S. Energy Information Administration (EIA). (2010). Environment: energy related emissions data & environmental analyses Retrieved from http://www.eia.doe.gov/en vironment.html U.S. Environmental Protection Agency. (2005). Using coal ash in highway construction: A guide to benefits and impacts. EPA 530 K 05 002. U.S. Geological Survey (USGS). (2012 ). Mineral Commodity Summaries Retrieved from http://minerals.usgs.gov/minerals/pubs/commodity/cement/ U.S. Geological Survey (USGS). (2011). Mineral Commodity Summaries Retrieved from http://minerals.usgs.gov/minerals/pubs/commodity/cement/ U.S. Geological Survey (USGS). (2010). Minerals Yearbook Retrieved from http://minerals.usgs.gov/minerals/pubs/commodity/cement/

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246 Venkatarama Reddy, B. V., & Jagadish, K. S. (2003). Embodied energy of common and alternative building materials and technologies. Energy and Buildings, 35 129 137 Wang, X., Nguyen, M., Stewart, M. G., Syme, M., Leitch, A. (2010). Analysis of Climate Change Impacts on the Deterioration of Concrete Infrastructure Synthesis Report. Published by CSIRO, Canberra. ISBN978 0 643 10364 1 World Business Council on Sustainable Development (WBCSD). (2010 ). Cement Sustainability Initiative Retrieved from http://www.wbcsdcement.org/index.php?option=com_content&task=view&id=174&Item id=232 Wang, J. C. and Yan, P. Y. (2006). Influence of initial casting temperature and dosage of fly ash on hydration heat evolution of concrete under adiabatic conditions. Journal of Thermal Analysis and Calorimetry, 85 (3), 755 760. World Business Council on Sustainable Developm ent (WBCSD). (2005). CO 2 accounting and reporting standard for the cement industry Retrieved from http://www.wbcsdcement.org/index.php/publications World Business Council on Sustainable Dev elopment (WBCSD). (2005). Guidelines for the selection and use of fuels and raw materials in the cement manufacturing process Retrieved from http://www.wbcsdcement.org/pdf/tf2_guidelines.pdf Zhang, F., Shen, D., Zhou, J., Li, Z. (2011). Effect of thermal environment at early age on hydration phases composition and strength development of concrete containing fly ash Advanced Materials Research, 168 170 582 588 Zhang, Y. M., Sun, W., & Yan, H. D. (2000). Hydration of high volume fly ash cement pastes. Cement and Concrete Composites, 22 445 452. Zhou, N. and McNeil, M. A. (2009). Assessment of Historic Trend in Mobility and Energy Use in India Transportation Sector Using Bottom up Approach Lawrence Berkeley National Laboratory (LBNL 2415E). Retrieved from http://china.lbl.gov/sites/china.lbl.gov/files/LBNL 2415E.pdf

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247 Appendix A Table A.1a Pervious C oncrete Literature

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2 48 Table A.1b Pervious C oncrete Literature cont.

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2 49 Table A.1c Pervious C oncrete Literature cont.

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2 50 Table A.1d Pervious C oncrete Literature cont.

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2 51 Table A.1e Pervious C oncrete Literature cont.

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2 52 Table A 2 A Comparison o f Literature Re garding Hot Weather Concreting or Thermal Properties of Fly Ash a nd High Volume Fly Ash Concrete.

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253 Appendix B Table B.1 Example of Fuel Emission Factors from Various Sources

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254 Figure B.1 Typical Cement Company Data on Fuel and Electricity Consumption from Annual Reports

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255 Appendix C Figure C .1 Coarse Aggregate Sieve a nd Other Lab oratory Analyses

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256 Figure C .2 Fine Aggregate Sieve a nd Other Laboratory Analyses

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257 Figure C .3 Autocad Drawing of the (a) Layout and (b ) Profile of the Pervious Concrete System (c ) Close Up of Profile (a) (b) (c)

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258 Appendix D (a) (b) Figure D .1 Vanakbori (a ) Compressive Strength Testing (b ) Fracture Paths (c) (d) Figure D .2 Gandhinagar (a ) Compressive Strength Testing (b ) Fracture Paths (a) (b) Figure D .3 7 Day Compressive Strength Testing Fracture Paths (a) Cylinders and (b ) Cubes

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259 (a) (b) Figure D .4 28 Day Compressive Strength Testing Fracture Paths (a) Cylinders a nd ( b ) Cubes (a) (b) Figure D .5 56 Day Compressive Strength Testing Fracture Paths (a) Cylinders and (b ) Cubes Figure D .6 OPC65W 56 Days Voids / But Paste i s Smoother

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260 (a) (b) Figure D .7 Fracture Pattern f or OPC Water Cured Samples (a ) 3 Days OPC55W (b ) 90 Days OPC55W (a) (b) (c) Figure D .8 Fracture Patterns and Texture f or OPC55H a t 90 Days Figure D.9 50FA55W at 1 D ay

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261 (a) (b) Figure D 10 50FA65W (a) a t 28 Days (b) Side Fracturing Occurring up Until 56 Days o f Testing Figure D.11 50FA55H P owdery at 56 days Figure D .12 Early Versus Later Age Breaking f or Heat Cured Fly Ash Samples (a ) 7 Day 50FA55H (b ) 90 Day 50FA55H

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262 (a) (b) Figure D .13 Early Versus Later Age Breaking f or Heat Cured OPC Samples (a) 3 Day OPC6 5H (b ) 90 Day OPC6 5H Heated Aggregate (a) (b) Figure D .14 Texture o f Water Cured OPC ( OPC55W ) Samples ( a ) Fracture Pattern ( b) Close Up o f Texture Pattern (a) (b) Figure D .15 ( a ) OPC55H HA Porous ( b ) OPC55H HA Characteristic of a Stalagmite a t 1 Day

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263 Figure D.16 Texture o f Fly Ash Water Cured ( 50FA65W ) Samples (a ) 90 Days Fracture and (b ) Close u p o f Texture (a) (b) Figure D.17 Texture of Fly Ash Heat Cured (50FA65H) Samples ( a) 90 Days Fracture a nd ( b) Close up o f Powdery Texture

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264 Regression Analysis: X versus A, B, C, D, T The regression equation is X = 6563 1777 A 379 B + 468 C 157 D + 6.48 T Predictor Coef SE Coef T P Constant 6562.7 249.4 26.31 0.000 A 1777.2 155.9 11.40 0.000 B 378.8 155.9 2.43 0.020 C 467.9 155.9 3.00 0.005 D 157.1 155.9 1.01 0.320 T 6.482 3.076 2.11 0.041 S = 540.204 R Sq = 78.2% R Sq(adj) = 75.6% Analysis of Variance Source DF SS MS F P Regression 5 43840803 8768161 30.05 0.000 Residual Error 42 12256459 291820 Total 47 56097263 Source DF Seq SS A 1 37899264 B 1 17216 71 C 1 2627664 D 1 296154 T 1 1296050 Unusual Observations Obs A X Fit SE Fit Residual St Resid 28 0.00 5100.0 6208.3 197.3 1108.3 2.20R R denotes an observation w ith a large standardized residual. Figure D .18 1 st Regression Analysis for X Standard Error of Predictor Variable = S/(S ) 1/2 T Test statistic for testing H o 1 =0 P value for testing H o 1 =0 Standard deviation of residuals Coefficient of determination, R 2 = SSR/SST*100 Adjusted value, the proportion of the variance of response explained by predictors Degrees of freedom for confidence intervals and significance tests Sum of Squares actual X bar ) 2 predicted X bar ) 2 actual X predicted ) 2 Mean Squares = SS/DF F Statistic = MSR/MSE testing that all coeff. are zero p value to determine significance, significant S k 2 k ) 2 /n k k Sequential Sum of Squares Standardized residuals greater than 2 or less than 2 identify an outlier and are calculated by dividing the residual by the standard deviation. (Refer to p. 720 in Hayter (1996) for standard deviation procedures)

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265 Regression Analysis: Y versus A, B, C, D, T The regression equation is Y = 3084 467 A + 1366 B 377 C + 86 D 5.77 T Predictor Coef SE Coef T P Constant 3084.1 376.7 8.19 0.000 A 467.2 235.5 1.98 0.054 B 1366.3 235.5 5.80 0.000 C 376.5 235.5 1.60 0.117 D 86.1 235.5 0.37 0.717 T 5.767 4.645 1.24 0.221 S = 815. 909 R Sq = 49.9% R Sq(adj) = 43.9% Analysis of Variance Source DF SS MS F P Regression 5 27837042 5567408 8.36 0.000 Residual Error 42 27959682 665707 Total 47 55796723 Source DF Seq SS A 1 2619245 B 1 22401629 C 1 1701303 D 1 88909 T 1 1025956 Unusual Observations Obs A Y Fit SE Fit Residual St Resid 19 1.00 3617 2079 298 1538 2.02R 29 0.00 6069 4214 2 63 1855 2.40R 30 0.00 6517 4017 302 2499 3.30R R denotes an observation with a large standardized residual. Figure D .19 1 st Regression Analysis for Y

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266 Regression Analysis: Z versus A, B, C, D, T The regression equation is Z = 0.00569 + 0.0181 A 0.0384 B + 0.00070 C 0.00649 D 0.000095 T Predictor Coef SE Coef T P Constant 0.005686 0.005790 0.98 0.332 A 0.018115 0.003620 5.00 0.000 B 0.03844 8 0.003620 10.62 0.000 C 0.000698 0.003620 0.19 0.848 D 0.006490 0.003620 1.79 0.080 T 0.00009506 0.00007139 1.33 0.190 S = 0.0125394 R Sq = 77.3% R Sq(adj) = 74.6% Analysis of Variance Source DF SS MS F P Regression 5 0.0224666 0.0044933 28.58 0.000 Residual Error 42 0.0066039 0.0001572 Total 47 0.0290705 Source DF Seq SS A 1 0.0039377 B 1 0.0177389 C 1 0.0000058 D 1 0.0005054 T 1 0.0002788 Unusual Observations Obs A Z Fit SE Fit Residual St Resid 22 1.00 0.01850 0.01661 0.00458 0.03511 3.01R 23 1.00 0.00875 0.01927 0.00405 0.02802 2. 36R R denotes an observation with a large standardized residual. Figure D .20 1 st Regression Analysis for Z

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267 Regression Analysis: X versus A, B, C, D, T, T*B The regression equation is X = 6042 1777 A + 663 B + 468 C 157 D + 15.5 T 18.0 T*B Predictor Coef SE Coef T P Constant 6041.9 277.1 21.80 0.000 A 1777.2 140.9 12.61 0.000 B 663.0 351.8 1.88 0.067 C 467.9 140.9 3.32 0.002 D 157.1 140.9 1.11 0.271 T 15.462 3.930 3.93 0.000 T*B 17.961 5.558 3.23 0.002 S = 488.115 R Sq = 82.6% R Sq(adj) = 80.0% Analysis of Variance Source DF SS MS F P Regression 6 46328739 77 21456 32.41 0.000 Residual Error 41 9768524 238257 Total 47 56097263 Source DF Seq SS A 1 37899264 B 1 1721671 C 1 2627664 D 1 296154 T 1 1296050 T*B 1 2487936 Unusual Observatio ns Obs A X Fit SE Fit Residual St Resid 28 0.00 5100.0 6477.8 196.8 1377.8 3.08R R denotes an observation with a large standardized residual. Figure D .21 2 nd Regression Analysis for X

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268 Regression Analysis: Y versus A, B, C, D, T, T*B The regression equation is Y = 4032 467 A 529 B 377 C + 86 D 22.1 T + 32.7 T*B Predictor Coef SE Coef T P Constant 4031.5 393.8 10.24 0.000 A 467.2 200.2 2.33 0.025 B 528.6 500.0 1.06 0.297 C 376.5 200.2 1.88 0.067 D 86.1 200.2 0.43 0.670 T 22.102 5.585 3.96 0.000 T*B 32.670 7.899 4.14 0.000 S = 693.672 R Sq = 64.6% R Sq(adj) = 59.5% Analysis of Variance Source DF SS MS F P Regression 6 36068334 6011389 12.49 0.000 Residual Error 41 19728390 481180 Total 47 55796723 Source DF Seq SS A 1 2619245 B 1 22401629 C 1 1701303 D 1 88909 T 1 1025956 T*B 1 8231292 Unusual Observations Obs A Y Fit SE Fit Residual St Resid 29 0.00 6069 4181 224 1888 2.88R 30 0.00 6517 4540 286 1976 3.13R R denotes an observation with a large standardized residual. Figure D .22 2 nd Regression Analysis for Y

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269 Regression Analysis: Z versus A, B, C, D, T, T*B The regression equation is Z = 0.00160 + 0.0181 A 0.0239 B + 0.00070 C 0.00649 D + 0.000030 T 0.000251 T*B Predictor Coef SE Coef T P Constant 0.001596 0.006934 0.23 0.819 A 0.018115 0.003526 5.14 0.000 B 0.023886 0.008805 2.71 0.010 C 0.000698 0.003526 0.20 0.844 D 0.006490 0.003526 1.84 0.073 T 0.00003047 0.00009836 0.31 0.758 T*B 0.0002511 0.0001391 1.80 0.078 S = 0.0122153 R Sq = 79.0% R Sq(ad j) = 75.9% Analysis of Variance Source DF SS MS F P Regression 6 0.0229527 0.0038254 25.64 0.000 Residual Error 41 0.0061178 0.0001492 Total 47 0.0290705 Source DF Seq SS A 1 0.00 39377 B 1 0.0177389 C 1 0.0000058 D 1 0.0005054 T 1 0.0002788 T*B 1 0.0004861 Unusual Observations Obs A Z Fit SE Fit Residual St Resid 22 1.00 0.01850 0.01285 0.00492 0.03135 2.80R 23 1.00 0.00875 0.01902 0.00395 0.02777 2.40R R denotes an observation with a large standardized residual. Figure D .23 2 nd Regression Analysis for Z

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270 Regression Analysis: X versus A, B, C, D, T, T*B The regression equation is X = 6014 1802 A + 804 B + 452 C 157 D + 15.3 T 18.4 T*B Predictor Coef SE Coef T P Constant 6014.0 196.9 30.54 0.000 A 1802.3 101.2 17.80 0.000 B 804.3 252.8 3.18 0.002 C 452.5 101.2 4.47 0.000 D 157.1 103.3 1.52 0.131 T 15.277 2.824 5.41 0.000 T*B 18.365 3.994 4.60 0.000 S = 554.557 R Sq = 76.9% R Sq(adj) = 75.7% Analysis of Variance Source DF SS MS F P Regression 6 115704778 19284130 62.71 0.000 Residual Error 113 34751308 307534 Total 119 150456086 Source DF Seq SS A 1 97443152 B 1 2041803 C 1 6142235 D 1 710771 T 1 2864197 T*B 1 6502620 Unusual Observations Obs A X Fit SE Fit Residual St Resid 17 0.00 5339.0 6540.3 141.9 1201.3 2.24R 72 1.00 6355.0 5190.5 141.9 1164.5 2.17R 79 0.00 5158.0 6574.7 145.9 1416.7 2.65R 80 0.00 5042.0 6574.7 145.9 1532.7 2.86R 83 0.00 4966.0 6383.2 149.2 1417.2 2.65R 92 0.00 5379.0 7027.2 145.9 1648.2 3.08R R denotes an observation with a large standardized res idual. Figure D .24 3 rd Regression Analysis for X

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271 Regression Analysis: Y versus A, B, C, D, T, T*B The regression equation is Y = 4032 467 A 529 B 377 C + 86 D 22.1 T + 32.7 T*B Predictor Coef SE Coef T P Constant 4031.5 330.5 12.20 0.000 A 467.2 168.1 2.78 0.007 B 528.6 419.7 1.26 0.211 C 376.5 168.1 2.24 0.028 D 86.1 168.1 0.51 0.610 T 22.102 4.688 4.71 0.000 T*B 32.6 70 6.630 4.93 0.000 S = 823.454 R Sq = 54.4% R Sq(adj) = 51.4% Analysis of Variance Source DF SS MS F P Regression 6 72136667 12022778 17.73 0.000 Residual Error 89 60348878 678077 Total 95 132485546 Source DF Seq SS A 1 5238489 B 1 44803259 C 1 3402606 D 1 177818 T 1 2051912 T*B 1 16462584 Unusual Observations Obs A Y Fit SE Fit Residual St Resid 35 1.0 0 2232.8 3986.9 240.5 1754.1 2.23R 44 1.00 1167.8 2955.2 234.7 1787.3 2.26R 56 0.00 2277.0 3885.0 234.7 1608.0 2.04R 57 0.00 6940.2 4180.9 188.2 2759.4 3.44R 60 0.00 7505.2 4540.2 240.5 2965.0 3.76R 93 1.00 1564.9 3337.1 188.2 1772.2 2.21R R denotes an observation with a large standardized residual. Figure D .25 3 rd Regression Analysis for Y

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272 Regression Analysis: Z versus A, B, C, D, T, T*B The regression equation is Z = 0.00160 + 0.0181 A 0.0239 B + 0.00070 C 0.00649 D + 0.000030 T 0.000251 T*B Predictor Coef SE Coef T P Constant 0.001596 0.006934 0.23 0.819 A 0.018115 0.003526 5.14 0.000 B 0. 023886 0.008805 2.71 0.010 C 0.000698 0.003526 0.20 0.844 D 0.006490 0.003526 1.84 0.073 T 0.00003047 0.00009836 0.31 0.758 T*B 0.0002511 0.0001391 1.80 0.078 S = 0.0122153 R Sq = 79.0% R Sq(adj) = 75.9% Analysis of Variance Source DF SS MS F P Regression 6 0.0229527 0.0038254 25.64 0.000 Residual Error 41 0.0061178 0.0001492 Total 47 0.0290705 Source DF Seq SS A 1 0.0039377 B 1 0.0177389 C 1 0.0000058 D 1 0.0005054 T 1 0.0002788 T*B 1 0.0004861 Unusual Observations Obs A Z Fit SE Fit Residual St Resid 22 1.00 0.01850 0.01285 0.00492 0.03135 2.80R 23 1.00 0.00875 0.01902 0.00395 0.02777 2.40R R denotes an observation with a large standardized residual. Figure D .26 3 rd Regression Analysis for Z