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Investigating soil-geotextile interaction mechanism

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Title:
Investigating soil-geotextile interaction mechanism
Creator:
Su, Cheng-Kuang
Place of Publication:
Denver, CO
Publisher:
University of Colorado Denver
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English
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xi, 164 leaves : illustrations ; 29 cm

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Subjects / Keywords:
Geotextiles -- Testing ( lcsh )
Geotextiles -- Testing ( fast )
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bibliography ( marcgt )
theses ( marcgt )
non-fiction ( marcgt )

Notes

Bibliography:
Includes bibliographical references (leaves 70-71).
Thesis:
Submitted in partial fulfillment of the requirements for the degree of Master of Science, Department of Civil Engineering
Statement of Responsibility:
by Cheng-Kuang Su.

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|University of Colorado Denver
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|Auraria Library
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All applicable rights reserved by the source institution and holding location.
Resource Identifier:
17997975 ( OCLC )
ocm17997975
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LD1190.E53 1986m .S82 ( lcc )

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Full Text
INVESTIGATING SOIL-GEOTEXTILE INTERACTION MECHANISM
by
Cheng-Kuang Su
B.S., Chung-Yang Christian University, 1980
A thesis submitted to the
Faculty of the Graduate School of the
University of Colorado in partial fulfillment
of the requirements for the degree of
Master of Science
Department of Civil Engineering
1986


This thesis for the Master of Science degree by
Cheng-Kuang Su
has been approved for the
Department of
Civil Engineering
by
Date
Atfjubdr.l ,/#&£


Su, Cheng Kuang (M.S., Civil Engineering)
Investigating Soil-Geotextile Interaction Mechanism
Thesis directed by Associate Professor Tzong H. ffu
Soil is inherently strong in compression, but weak in
tension. The concept of reinforcing an earth fill by incor-
porating materials which possess a much higher tensile
strength than soil and the capability of bonding with soil
through friction has recently begun to gain popularity in the
United States. Among various materials which have been used
as reinforcement, woven and non-woven fabrics (ASTM: "geotex-
tile"), have demonstrated great potential in such applications
as embankments over soft ground, earth-retaining walls, found-
ation mats, and contaminant dikes.
In order to investigate the soil-geotextile inter-
action mechanism, a test was designed in which the geotextile
is stressed in tension and is confined in soil. The soil bin
is 48 inches by 24 inches in plane and 57 inches high. In the
test, a large-size geotextile is embedded in the soil and
incremental pulling forces are imposed on a sheet metal clamp
which secures the geotextile specimen along its width. The
displacement at the end of the geotextile where the load is
applied as well as the displacements along the length of the
geotextile were measured. A new procedure for placing the
backfill was devised to ensure uniform density in the soil
bin. One important aspect of the test is that the geotextile
must be kept in the confinement of soil throughout the test.


iv
This is necessary in order to measure the displacement at the
end of the geotextile where the load is applied, to facilitate
control of the applied forces, and to avoid breakage of
geotextile specimen as it becomes exposed to the air.
Displacement patterns of four tests, conducted at an
approximately constant soil density, were evaluated to examine
the soil-geotextile interaction mechanism for the imposed
loading condition. It is to be noted that the tests also
provide invaluable controlled test data for verification of
numerical models, which, upon establishing their reliability,
can be used to investigate the soil-geotextile interaction
mechanism in geotextile-reinforced earth structures.


ACKNOWLEDGEMENTS
The study described herein was performed under the
supervision of Professor Tzong H. Wu. I am grateful for his
support and encouragement throughout my academic and research
program. Gratitude is also extended to James Crofter for
providing numerous fruitful suggestions in the design of the
test equipment in this research. Further special thanks are
extended to Barry Siel and Hsing-Cheng Liu for providing their
test data and to Hsien-Hsiang Chiang and Victor C. C. Yang for
their help in preparation of this thesis.
This research work was sponsored by the National
Science Foundation and their support is gratefully
acknowledged.


CONTENTS
CHAPTER PAGE
1. INTRODUCTION..................................... 1
1.1 Problem Statement ............................ 1
1.2 Study Objective .............................. 3
1.3 Method of Study............................... 4
2. TEST APPARATUS AND INSTRUMENTATION................... 5
2.1 Description of Test Apparatus................. 6
2.1.1 Pullout Test Setup .................. 6
2.2.2 Pullout Force Application Setup . 6
2.2.3 Surcharge Load Application Setup 11
2.2.4 Soil Placement Device .............. 11
2.3 Instrumentation and Measurement ............. 16
3. LARGE BOX PULLOUT TEST............................ 26
3.1 Material Properties ........................ 26
3.1.1 Soil Index Properties .............. 26
3.1.2 Geotextile Properties .............. 26
3.1.3 Frictional Properties .............. 29
3.2 Sample Preparation ................... 29
3.2.1 Small-Scale Raining Device Trial
Tests............................... 29
3.2.2 Sample Preparation Procedures 32


vii
CHAPTER PAGE
4. TEST RESULTS AND DISCUSSION OF RESULTS .... 38
4.1 Applied Loads Versus the Clamped-End
Movements .................................... 40
4.2 Applied Loads Versus Movement Along the
Geotextiles .................................. 47
4.3 Applied Loads Versus Deformation Along
the Geotextiles .............................. 52
4.4 Tensile Force Distribution Along the
Geotextiles .................................. 57
5. SUMMARY AND CONCLUSIONS ............................. 67
5.1 Summary ...................................... 67
5.2 Conclusions .................................. 68
BIBLIOGRAPHY ............................................... 70
APPENDIX
A. PULLOUT FORCE CORRECTION ............................ 72
B. MAGNET MOVEMENTS DATA SHEETS ........................ 78


LIST OF TABLES
TABLE PAGE
3.1 Properties of Trevira 1127 (Trevira Catalog) . 28
3.2 Results of Small-Scale Raining Tests ............. 33
4.1 Large Pullout Tests
39


LIST OF FIGURES
FIGURE PAGE
2.1 Large Pullout Test Setup
(a) Plan View (b) Side View................ . 7
2.2 . Pullout Test Setup........................ 8
2.3 Soil Bin for Large Pullout Test............. 9
2.4 Loading Frame and Hydraulic Jack Used for
Supplying Load..................................... 10
2.5 Exploded View of Sheet Metal Clamp
(a) Top View (b) Side View ........................ 12
2.6 Wooden Panels for Surcharge Load Application . 13
2.7 Uniform Raining Device ............................ 14
2.8 Soil Leveling Device........................ 15
2.9 Pullout Force-Clamp Displacement Measurement
Setup.............................................. 17
2.10 Hall Generator Probe Setup.................. 18
2.11 Magnet Movements Tracing Device ................... 19
2.12 Placement of Outer Tube Above Geotextile ... 20
2.13 Magnet Response Recorded by X-Y Recorder ... 21
2.14 Electronic Monitoring Device ...................... 22
2.15 X-Y Recorder for Recording Magnetic Field ... 23
2.16 Digital Multimeter ................................ 25
3.1 Grain Size Distribution ........................... 27
3.2 Methods for Showering Sand.................. 30
3.3 Small-Scale Raining Device ........................ 31


X
FIGURE PAGE
3.4 Placement of Magnets on Geotextile Surface . 34
3.5 The Application of Leveling Device.................. 36
4.1 (a) Geotextile Specimen Failure, Test 1 . . . . 41
(b) Geotextile Specimen Failure, Test 2 ... . 41
(c) Geotextile Specimen Failure, Test 3 . . . . 42
(d) Geotextile Specimen Failure, Test 4 . . . . 42
4.2 (a) Applied Load Versus Clamped-End Movement,
Test 1......................................... 43
(b) Applied Load Versus Clamped-End Movement,
Test 2.......................................... 44
(c) Applied Load Versus Clamped-End Movement,
Test 3.......................................... 45
(d) Applied Load Versus Clamped-End Movement,
Test 4.......................................... 46
4.3 (a) Applied Load Versus Cumulative Displacements
Along the Length of Geotextile, Test 1 . . 48
(b) Applied Load Versus Cumulative Displacements
Along the Length of Geotextile, Test 2 . . 49
(c) Applied Load Versus Cumulative Displacements
Along the Length of Geotextile, Test 3 . . 50
(d) Applied Load Versus Cumulative Displacements
Along the Length of Geotextile, Test 4 . . 51
4.4 (a) Applied Load Versus Deformations Between
Magnet Stations, Test 1 53
(b) Applied Load Versus Deformations Between
Magnet Stations, Test 2 54
(c) Applied Load Versus Deformations Between
Magnet Stations, Test 3 55
(d) Applied Load Versus Deformations Between
Magnet Stations, Test 4 56
(a) Deformation Along the Geotextile, Test 1 . 58
4.5


xi
FIGURE PAGE
(b) Deformation Along the Geotextile, Test 2 59
(c) Deformation Along the Geotextile, Test 3 . 60
(d) Deformation Along the Geotextile, Test 4 . 61
4.6 The Strain Distribution Along the Length of
Geotextile in Test 3 for 450 lb Applied Load . 62
4.7 (a) Load-Deformation of the Geotextile Tested
in the Confinement of soil..................... 64
(b) The In-Soil Stress-Strain Relationship
of the Geotextile ............................. 65
4.8 The Force Distribution in the Geotextile
for the Applied Load of 450 lb, Test 3 . . . 66


CHAPTER 1
INTRODUCTION
1.1 Problem Statement
Soil is inherently strong in compression, but weak in
tension. The concept of reinforcing an earth fill by incor-
porating materials which possess a much higher tensile
strength than soil, and the capacity to bond with soil through
friction has been utilized quite extensively in Europe, but
only recently has the concept begun to gain popularity in the
United States. To date, over 5,000 reinforced earth projects
have been completed worldwide and they have repeatedly demon-
strated superior structural performance, ease and speed of
construction, and low costs compared with alternatives in such
applications as embankments over soft ground, earth retaining
walls, bridge abutments, contaminant dikes, foundation mats,
and bulk storage and handling facilities.
Both raw materials and manufactured products have been
used for earth reinforcement. The best-known earth-reinforcing
technique, primarily applied to retaining walls, was developed
in France by H. Vidal, and most research heretofore has
concentrated on this technique. In the Vidal technique, thin
strips of aluminum or steel are placed horizontally in layers
behind a relatively thin concrete or metal "facing," and then


2
the wall is backfilled in layers with soil. Symons (1973), in
an excellent review of research in both France and the United
States on the Vidal technique, pointed out a major problem
concerning the method -- the long-term durability of the
metallic reinforce- ment. The usual practice, at least in the
U.S. is to increase the thickness of metal strips to allow for
corrosion (Lee, et al., 1973). However, as with other buried
metallic structures such as steel piles, culverts,
etc. corrosion rates are highly unpredictable, and it is this
uncertainty that makes the Vidal technique less attractive for
permanent construction.
One viable alternative reinforcing technique is to use
woven and nonwoven fabric materials (ASTM : "geotextile") as
the reinforcing element. This technique has been applied to
embankments over soft foundation (Wager, 1968; Holtz, 1975;
Bell, et al., 1977; Maagdenberg, 1977; Fowler and Haliburton,
1980; Fowler, 1981; Barsvary, et al., 1982), retaining walls
(Bell and Steward, 1977; Douglas, 1982; Bell, et al., 1983),
slope reinforcement (Iwasaki Andwatanabe, 1978; Murray, 1981
and 1982), and bearing capacity improvement of shallow
foundations (Guido, et al., 1985).
In general, geotextiles are more economical, more
easily handled and constructed, and stronger in resisting
corrosion and bacterial action than many traditional materials
including metals. Moreover, when geotextiles are used as
reinforcement, they also serve many other functions such as
separation, drainage, and filtration.


3
Geotextile-reinforced earth structures, however,
suffer from a major disadvantage there is a total lack of
understanding as to the reinforcing mechanism. As a result,
the design procedures are very empirical and not based on
sound engineering research.
1.2 Study Objective
The objective of this study is to establish controlled
test data for investigation of the soil-geotextile interaction
mechanism of geotextile-reinforced earth structures.
The interaction mechanism of geotextile-reinforced
earth structures is complicated. As a general rule, when a
geotextile-reinforced earth mass deforms under applied loads,
the geotextile will be subjected to tension provided that
there is adequate frictional resistance between the geotextile
and soil. As a result, not only will the stresses in the soil
mass be redistributed into a more favorable state, the
geotextile will react along the surrounding soil, increasing
its effective confinement and, hence its stiffness.
The extent of the stress redistribution depends on the
relative stiffness of the geotextile and the soil, which are
both nonlinear in nature, as well as the loading geometry of
the geotextile-reinforced earth structures. In order to in-
vestigate the soil-geotextile interaction mechanism of dif-
ferent applications of geotextile reinforcement under various
conditions, it is essential to develop a numerical model which
can realistically and reliably analyze the problem.


4
The purpose of this study is to provide controlled
test data for validation of the analytical model. The test
results will also give engineers insight into the soil-geotex-
tile interaction mechanism under the test conditions.
1.3 Method of study
Laboratory pullout test is a test which many research-
ers consider an adequate representation of the real phenomenon
that occurs in reinforced earth structures and gives values of
soil-reinforcement friction coefficient used for design pur-
poses. In the pullout test, a geotextile specimen is embedded
in the soil which is confined in a box and is subjected to an
overburden pressure. Incremental pullout forces are imposed
on one end of the geotextile specimen so that the geotextile
is subject to tension. Relative movement between the soil and
geotextile will occur as the geotextile itself deforms and/or
the frictional resistance is mobilized.
In this study, a large scale pullout test was designed
and constructed. The soil bin is 48 inches by 24 inches in
plane and 57 inches high. A new procedure for placing the
soil was devised to ensure uniform density in the soil bin. A
total of four tests were conducted. The displacement at the
end of the geotextile specimen where the load is applied as
well as the displacements along the length of the geotextile
were measured.


CHAPTER 2
TEST APPARATUS AND INSTRUMENTATION
In this study, a large pullout test apparatus was
designed and manufactured. The displacements along the length
of the geotextile were measured. The geotextile was confined
in soil prepared at a constant density. The soil was subject
to a constant vertical load. Since the geotextile must be
kept in the confinement of the soil throughout the test, one
end of the geotextile specimen was glued between a steel sheet
metal clamp which is partially embedded in the soil. This
prevented unrestrained stretching of the geotextile as it
comes out of the pullout box and ensured uniform straining
along the width of the geotextile.
An electronic monitoring system including a Hall
generator probe, a X-Y recorder and a digital multimeter was
used to measure displacements of the geotextile. This was
accomplished by measuring movements of magnets which were
glued at 1.5 to 3 inches intervals along the length of the
geotextile surface. The measurement was made by inserting a
Hall generator probe with a magnetic sensor into a glass tube
which was embedded in the soil immediately above the center
line of the geotextile. The movements of the magnets were


6
recorded after each pullout force increment was applied to the
geotextile.
2.1 Description of Test Apparatus
2.1.1 Pullout Test Setup
The pullout test setup consisted of a steel angle
reinforced plywood box and a set of steel tube loading frames
with a hydraulic jack reacting against the box to apply
pullout forces. The pullout test setup is shown in Figures
2.1 and 2.2.
As depicted in Figure 2.3, the pullout box was con-
structed from 0.75 inch thick plywood panels on three sides,
and on one side by a 0.75 inch thick acrylic sheet to allow
for visual observation of the box interior. The box is 57
inches high with 48 inches by 24 inches in plane. The sides
and bottom of the box were secured by using 0.25 inch thick
steel angle sections. The four sides of the wall were re-
inforced by cross-ties at two levels with 0.5 inch diameter
steel bars.
In order to minimize the side wall friction between
the box and soil, the interior wall surfaces were lined with a
layer of 1/16 inch thick smooth surface geomembrane.
2.2.2 Pullout Force Application Setup
A steel tube loading frame with hydraulic jack was
designed and built as shown in Figure 2.4. The equipment
assembly consisted of a 10 ton capacity hydraulic jack using


7
Clamp
Surcharge
Figure 2.L : Large Pullout Test Setup
(a) Plan View (b) Side View
TuvuvVmvuv


8
Figure 2.2 : Pullout Test Setup


9
Figure 2.3 : Soil Bin for Large Pullout Test


10
Figure 2.4 : Loading Frame and Hydraulic Jack Used
for Supplying Load


the steel frame to react against the pullout box for appli-
cation of pulling forces.
The connection between the pulling mechanism and the
sheet metal clamp was designed to allow for free rotation in
the horizontal plane. The arrangement of the connection is
illustrated in Figure 2.5.
2.2.3 Surcharge Load Application Setup
Dead load was used to supply overburden pressure over
the geotextile. The dead load consisted of 36 inch height of
sand in the soil bin and 24 sand bags which were placed on
wooden panels lying on top of the soil. Figure 2.6 shows the
arrangement of the wooden panels.
2.2.4 Soil Placement Device
In an attempt to place the sand in the pullout box at
an uniform density, a "uniform raining device shown in Figure
2.7 was devised. The device is a rectangular bin fitting the
inside dimension of the pullout box. There are a screen and a
two-piece door attached to the bottom of the bin. The door
can be opened by releasing cables which are mounted above the
soil bin. Detailed procedure of its application is given in
Chapter 3.
In addition, a leveling device was designed to level
the top of the sand prior to placing the geotextile in the
pullout box. The leveling device, shown in Figure 2.8, is
made of a leveling blade attached to two parallel supporting
columns which are hung on a steel tube crossing the top of the


12
(a) Top View
Figure 2.5 : Exposed View of Sheet Metal Clamp
(a) Top View (b) Side View


13
Figure 2.6: Wooden Panels for Surcharge Load Application


14
Figure 2.7
Uniform Raining Device


15
i
Figure 2.8
Soil Leveling Device


16
pullout box. Procedure for its use is also described in
Chapter 3.
2.3 Instrumentation and Measurement
A dynamometer was used to determine applied pullout
forces. The maximum capacity of the dynamometer is 8,000 lb
with 50 lb in a division. The 50 lb loading increment was
employed for the test. After each load increment was applied,
the displacement of the sheet metal clamp was measured by
using a dial gage with 0.001 inch an inch accuracy (Figure
2.9). The movements along the length of the geotextile were
measured by a Hall generator probe-magnet system. The magnets
of 0.06 inch thickness and 1/16 inch diameter were glued along
the centerline of the geotextile surface at an interval of 1.5
to 3 inches. The Hall generator probe was housed in a 0.312
inch diameter inner tube (Figure 2.10 and Figure 2.11). For
tracing the magnet movements, the probe is inserted into the
pullout box through a 0.405 in diameter outer tube, which was
placed immediately above the magnets during soil placement
(Figure 2.12). The Hall generator probe responds to a mag-
netic field in a very sensitive manner. Figure 2.13 shows the
response of the probe to a series of magnets in the form of
sine waves. The sine waves were generated by an electronic
monitoring device (Figure 2.14) and recorded by a X-Y recorder
(Figure 2.15). In the plots, X-axis represents the distance
whereas Y-axis record the intensity of the magnetic field.
The location of a magnet is at which the Y-axis plot reaches a


17


Figure 2-10 : Hall Generator Probe Setup
oo


19

Figure 2.11 : Magnet Movements Tracing Device


20
Figure 2.12 : Placement of Outer Tube Above Geotextile


Hn
21
Figure 2.13 : Magnet Response Recorded by X-Y Recorder


22
Figure 2.14 : Electronic Monitoring Device


23


24
maximum (e.g., points A, B, C, and D in Figure 2.13). In
order to determine more precisely the movements of the
magnets, a digital multimeter was used (Figure 2.16). When
the Hall generator probe is directly above a magnet, as
indicated by the X-Y recorder, the digital number on the
multimeter indicates the distance of the probe movement. The
accuracy of the measurement is + 0.01 inch.


25
Figure 2.16 : Digital Multimeter


CHAPTER 3
LARGE BOX PULLOUT TEST
3.1 Material Properties
3.1.1 Soil Index Properties
The soil used in this study was a uniform Ottawa
sand. The grain size distribution curve of the sand is shown
in Figure 3.1. The uniformity coefficient of the sand is
1.43. The sand has subrounded grain shape and the specific
gravity is 2.65. The minimum and maximum dry density were
determined by Liu (1985) in accordance with the procedure
given in Appendix E-12 on "Relative Density of Cohesionless
Soil" of the earth manual (2nd Edition, 1974) as:
Maximum Density = 112.19 pcf
Minimum Density = 97.52 pcf
In the study, the soil is prepared at a density of
107 pcf. Results of the triaxial compression tests indicated
that the angle of internal friction is 37 degree.
3.1.2 Geotextile Properties
The geotextile used in the pullout test is a 100% poly-
ester continuous spun needle punched fabric (Trevira 1127).
Table 3.1 shows the properties of the geotextile given by
the manufacturer. The geotextile specimens used in the tests


27
Q>
C
c

o

CL
o> in *- o o o r m
T- ps. TT CM m N.
CO o
b b o o'
Grain diameter, mm
Figure 3.1
Grain Size Distribution (Liu, 1985)


28
Table 3.1 : Properties of Trevira 1127 (Trevira Catalog, 1984)
1 2 Fabric Weight (oz/yd ) 8
2 Thickness (Mils) (ASTM D-1777) 125
3 Grab Strength (lb, MD/CD) (ASTM D-1682) 260/225
4 Grab Elongation (%, MD/CD) (ASTM D-1682) 85/95
MD = Machine Direction
CD = Cross Machine Direction


29
were 18 inches wide with three different lengths: 27, 18, and
12 inches.
3.1.3 Frictional Properties
The friction angle between the soil and sheet metal,
which was the material used for the metal clamp in the pullout
test, was determined to be 16.5 degrees. The friction angle
between the soil and the geomembrane that was used to line the
interior of the pullout box was found to be equal to 18.5
degrees. Both were obtained from direct shear tests with a
soil density of 107 pcf.
3.2 Sample Preparation
3.2.1 Small-Scale Raining Device-Trial Tests
From published literature, sand placement in large
scale tests has usually been carried out by using showering
methods as illustrated in Figure 3.2. These showering
methods, however, were not used in this study, because it was
believed that a uniform raining method would give better
results. In order to gain some experience with the uniform
raining device, a small-scale test apparatus, shown in Figure
3.3, was first constructed. The apparatus consisted of two
containers with one fitting inside of the other. The outside
container has interior dimensions of 1 ft by 1 ft by 1 ft.
The inside container has a screen attached to its bottom for
sand to rain through. The screen was identical to the one
used for the uniform raining device (Chapter 2). A series of


5
V
METHOD B
METHOD C
Centrol pouring,creoting "Combined funnels" pouring,
sloped surfoce. creoting o flof surfoce
(loose sdnd) (dense sand)
Figure 3.2 : Methods for Showering Sand
(Whitman, et al., 1962)
Pouring through muzzle-
pipe, creoting o flat
surface (dense sand)
t
LO
O


Figure 3.3 : Small-Scale Raining Device


32
tests was conducted with the small-scale raining device. The
results are presented in Table 3.2. It is seen that the
device provides a consistent means for placing the sand
uniformly in a container. With a rain height of 15 inches the
soil density is approximately 107 pcf.
3.2.2 Sample Preparation Procedures
The procedures for sample preparation are described in
the following:
1) trim the geotextile specimen to the selected
s ize;
2) glue magnets to the surface of the geotextile at
pre-determined intervals of 3 inches along the
centerline of the geotextile (Figure 3.4), leave
overnight for the glue to set;
3) cover the magnets with scotch tape to provide a
more even surface;
4) attach the "uniform raining" device on the top of
the pullout box to allow for a rain height of 15
inches above the sand surface;
5) place a predetermined amount of sand (to form
approximately 2.5 in. soil layers in the box) in
the uniform raining device and level the surface
in the device;
6) release cables to open up the doors at the bottom
of the uniform raining device and allow the sand
to "rain" uniformly in the pullout box;


Table 3.2 : Results of Small-Scale Raining Tests
Test Height of Rate of Unit
No. Free Fall Flow Weight
(in.) (ft^/min.) (pcf)
1 1 0.73 102.6
2 1 0.75 102.5
3 1 0.74 102.5
4 15 0.75 107.3
5
15
0.74
107.2


Figure 3.4
Placement of Magnets on Geotextile Surface


35
7) raise the uniform raining device to a height of 15
inches above the new soil surface;
8) place the same amount of sand in the uniform
raining device and allow the sand to "rain" in the
box in the same manner as step 6;
9) repeat steps 5 through 8 until the soil surface
reaches the height of the front slot;
10) use additional sand (preweighed) to rain through
the four edges of the uniform raining device to
obtain a more level surface;
11) remove the uniform raining device and use the
leveling device (see Chapter 2) to ensure a level
surface (Figure 3.5);
12) place the geotextile specimen on the top of sand
surface and line up the specimen with the center-
line of the sheet metal clamp;
13) rest the glass tube immediately above the magnets;
14) repeat steps 5 through 8 to place an additional 20
inches of sand above the geotextile specimen;
15) remove the uniform raining device and level the
top layer of the soil surface;
16) measure the height of the specimen and calculate
the density of the sand;
17) place a sheet of plastic on the top of the
specimen for calculations of the unit weight after
the test;
place additional sand to fill the pullout box;'
18)


Figure 3.5 : The Application of Leveling Device


37
19) place 24 sand bags on the plywood panel resting on
the sand surface to simulate the overburden
pressure. In the study, the total load above the
geotextile amounts to an equivalent overburden
pressure of 4.34 psi.


CHAPTER 4
TEST RESULTS AND DISCUSSION OF RESULTS
In this study, four geotextile samples of three
different lengths with a constant width were tested. The soil
was prepared at a density of approximately 107 pcf. The
geotextile was subject to 4.34 psi of overburden. A constant
increment of 50 lb pulling force was applied to the geotex-
tile. Measurement of the movements of the geotextile along
its length was taken as each load increment was applied. The
test condition of the four pullout tests is summarized in
Table 4.1.
All the tests were conducted until a failure condition
developed. The failure condition is defined herein as the
limiting condition at which significant movement of the
geotextile occurred abruptly and continuously. As the failure
load was reached, the load would drop rapidly and it would not
be possible to maintain the loading level.
Except for Test 1, failure condition developed in the
form of "pullout", i.e., the failure load was reached after
the frictional resistance at the soil-geotextile interface had
been fully mobilized. In these cases, movement at the free-
end initiated prior to the failure load was applied. In
Test 1, due to the length of the specimen, the free-end did


39
Table 4.1 : Large Pullout Tests
Test No. Geotextile Specimen Length (in.) Geotextile Specimen Width (in.) Soil* Density (pcf) Overburden Above the Geotextile (psi)
1 27 18 106.2 4.34
2 18 18 107.2 4.34
3 12 18 107.1 4.34
4 12 18 107.0 4.34
: The soil density was determined prior to application
overburden; at the end of the tests, the densities were
found to increase approximately by 0.5 pcf.


40
not move throughout the test. Failure in Test 1 was a result
of yielding of the geotextile. The configuration of the
specimens upon the completion of the tests are shown in
Figure 4.1.
4.1 Applied Loads Versus the Clamped-end Movements
The loading history and the relationships between
applied pulling forces and the clamped-end movements of the
four tests are depicted in Figure 4.2.
The left side of the figure shows the loading history.
The loads were applied at a constant increment of 50 lb. As
the movement of the geotextile occurred in response to a load
increment, it was accompanied by a reduction in the force
exerted by the hydraulic jack. The reductions are shown in
the figure as dashed lines. In Tests 1 and 2, the reductions
were fairly significant. This was partially because there was
a faulty valve in the hydraulic jack. The problem was
corrected before conducting Tests 3 and 4.
The right side of Figure 4.2 shows the applied load
versus clamped-end movement. As may be expected, the
load-deformation characteristics were approximately the same
for all four tests in the early portion of the loading
history; Tests 3 and 4, with a shorter geotextile specimen,
reached the failure condition at smaller loads than Tests 1
and 2. It is of interest to note that Test 1, with a longer
geotextile specimen, failed at a smaller load than Test 2.
This is due to the fact that Test 1 did not fail in the same


41
Figure 4.1 (a) : Geotextile Specimen After Failure, Test 1
Figure 4.1 (b)
Geotextile Specimen After Failure, Test 2


42
Figure 4.1 (d) : Geotextile Specimen After Failure, Test 4


43
->l H-
D
Figure 4.2 (a) : Applied Load Versus Clamped-End
Movement, Test 1


44
Load Increment No. Clamped-End Movement, D (in.)
Figure 4.2 (b) : Applied Load Versus Clamped-End
Movement, Test 2


45
Load Increment No. Clamped-End Movement, D (in.)
Figure 4.2 (c) : Applied Load Versus Clamped-End
Movement, Test 3


46
Load Increment No. Clamped-End Moyement, D (in.)
Figure 4.2 (d) : Applied Load Versus Clamped-End
Movement, Test 4


47
mode as the other tests. In Test 1, yielding of the geotex-
tile dictated the failure condition as the free-end did not
move throughout the tests. This observation indicated a very
important design consideration -- yielding (rupture) of geo-
textiles can be a governing factor in design of geotextile-r
reinforced earth structures.
Tests 3 and 4 were conducted with presumably identical
conditions. The difference in the test results (of approxi-
mately 50 lb load ) was attributed primarily to the difficulty
in lining up the pulling mechanism on a level plane with the
geotextile specimen at the beginning of the tests.
It should be noted that since the applied forces were
partially resisted by the friction between the metal clamp and
the confining soil, the forces applied to the geotextile had
to be corrected by subtracting the frictional forces over the
embedded area of the metal clamp from the corresponding
applied forces. The corrections are summarized in Appendix
A. All the applied loads reported in this chapter are
corrected loads unless specified otherwise.
4.2 Applied Load Versus Movements Along the Geotextiles
Figure 4.3 shows the relationships between the loads
applied to the clamped-end of the geotextile and the cumula-
tive movements along the length of the geotextile.
The cumulative movements in the geotextile were mea-
sured by the Hall generator probe-magnet system at selected
points. The movements represent the compound effect of


48
Figure 4.3 (a) : Applied Loads Versus Cumulative Displacements
Along the Length of Geotextile, Test 1


49
Figure 4.3 (b) : Applied Loads Versus Cumulative Displacements
Along the Length of Geotextile, Test 2


50
Figure 4.3 (c) : Applied Loads Versus Cumulative Displacements
Along the Length of Geotextile, Test 3


51
Figure 4.3 (d) : Applied Loads Versus Cumulative Displacements
Along the Length of Geotextile, Test 4


52
stretching of the geotextile and the sliding against the soil.
Ten magnet stations were used in Test 1. Tests 2, 3, and 4
used 9 magnets. The layout of the magnet stations are
depicted in Figure 4.3. The shaded area in Figure 4.3 (a)
illustrates the portion of geotextile that remains stationary
in Test 1. Measurements of magnet movement of the four tests
are presented in Appendix B.
As can be expected, the movement of the geotextile
began at the clamped-end where, the load was applied and gradu-
ally propagated toward the free-end as the load increased.
4.3 Applied Loads Versus Deformations Along the Geotextile
Geotextile is a "deformable" material. When a tension
load increment is applied to one end of an embedded geotextile
specimen, the movement of the geotextile is due entirely to
stretching of the geotextile itself until a large enough load
is reached so that sliding of the entire specimen against the
soil begins to take place.
Figure 4.4 illustrates the deformation (stretching)
along the length of the geotextile in response to applied
loads for the four tests. It is shown that the deformation
initiates at the clamped-end and propagated toward the
free-end as the load increased. The darkened area of Test 1
specimen indicated the region that remained stationary in the
test. The shaded area of Tests 2, 3, and 4 specimens shows
the portion of the geotextile in which deformation has not
developed before sliding of the specimens occurs.


53
Figure 4.4 (a) : Applied Loads Versus Deformations
Between Magnet Stations, Test 1


54
Figure 4.4 (b) : Applied Loads Versus Deformations
Between Magnet Stations, Test 2


Figure 4.4 (c) : Applied Loads Versus Deformations
Between Magnet Stations, Test 3


Applied Load, P (lb)
Figure 4.4 (d) : Applied Loads Versus Deformations
Between Magnet Stations, Test 4


57
The load-deformation curves are seen to have a slight
degree of fluctuation especially near the clamped-end where
the imposed loading history illustrated in Figure 4.2.
Results of Tests 3 and 4, which were conducted in
presumably the same conditions, were nearly identical when
shifting the load by a 50 lb difference. This is consistent
with the observations discussed in Section 4.1.
Figure 4.5 depicts the deformations along the geotex-
tiles at different load levels for the four tests. As a
general rule, it is seen that the deformation along the
geotextile reduced toward the free-end. The rate of reduction
increases as the load level increases.
4.4 Tensile Force Distribution Along the Geotextile
The tensile force distribution in the geotextile
specimens at a given applied load can be determined from the
strain distribution along the length of the geotextile and the
load-deformation relationship of the geotextile under the same
test conditions as the pullout tests. The following shows how
to obtain the force distribution using results of Test 3 as an
example.
The strain distribution along the length of the
geotextile in Test 3 for an applied load of 450 lb at the
clamped-end is shown in Figure 4.6. The strain distribution
was computed by dividing the deformation (stretching) of the
geotextile between any two magnet stations (Figure 4.5 (c)) by
initial distance between the magnet stations.


Deformation (in.
58
Applied Load, P (lb)
Magnet Station No.
Figure 4.5 (a) : Deformations Along the Geotextile, Test 1


Deformation (in.
Applied Load, P (lb)
Figure 4.5 (b) : Deformations Along the Geotextile, Test 2


60
0.5
C5
H
c
o
H
4J
&
u
o
U-i
o
0.0
Magnet Station No.
Figure 4.5 (c) : Deformations Along the Geotextile, Test 3


61
4 3 2 1
Applied Load, P (lb)
0.5 -
a
o
ca
S
u
o
>4-1
a)
a
0.0
Figure 4.5 (d) : Deformations Along the Geotextile, Test 4


Strain (%)
62
Figure 4.6 : The Strain Distribution Along the Length
of the Geotextile in Test 3 for 450 lb
Applied Load


63
Figure 4.7 (a) shows the load-deformation curve of the
geotextile tested in the confinement of soil. The curve was
obtained by employing a specially designed apparatus with the
same soil type, the same geotextile, the same soil density,
and the same overburden pressure as Test 3 in this study. The
test apparatus was developed by Siel (1986).
The in-soil stress-strain relationship of the geotex-
tile, which was deduced from Figure 4.7 (a), is illustrated in
Figure 4.7 (b).
By combining Figures 4.6 and 4.7 (b), the force
distribution in Test 3 for the applied load of 450 lb could be
determined as shown in Figure 4.8.


300
~ 200 Xi
0-.
T3 cd o .J /
(U rH /
rH a a. < 100 /
0 L i i i 1 0.0 0.3 0.6 0.9 1.2 Deformation (in.)
Figure 4.7 (a) : The Load-Deformation of the Geotextile
Tested in the Confinement of Soil


Stress (psi)
65
Figure 4.7 (b) : The In-Soil Stress-Strain Relationship
of the Geotextile


66
600.-
400

u
u
o
200
0
J----------1___________
2 3 4 5
Magnet Station No.
Figure 4.8 : The Force Distribution in the Geotextile
for the Applied Load of 450 lb, Test 3


CHAPTER 5
SUMMARY AND CONCLUSION
5.1 Summary
In this study, experimental tests were performed to
investigate soil-geotextile interaction behavior in the pull-
out test. A large pullout test apparatus was designed and
manufactured for this study. The soil bin is 48 inches by 24
inches in plane and 57 inches high, constructed with 0.75 inch
thick plywood by using steel angle sections to secure the
sides and bottom. There is a 0.5 inch wide slot on the front
side of the bin to attach the geotextile to a loading
mechanism.
In the tests, a large size non-woven geotextile was
embedded in a granular soil of a constant uniform density and
incremental pulling forces were imposed on a sheet metal clamp
which secured the geotextile specimen along its width. The
displacement at the clamped-end of the geotextile as well as
the displacements along the length of the geotextile were
measured by a Hall generator probe-magnet system.
A total of four tests were performed. The tests
varied in specimen length and were conducted until a "failure
condition was reached. The study should provide invaluable


68
controlled test data for verification of numerical modeling of
soil-geotextile interaction.
5.2 Conclusions
The findings and conclusions of this study are
summarized in the following:
1) The large test setup devised in this study can be
used to conduct pullout test satisfactorily and
gives consistent test results.
2) In order to conduct pullout test of geotextiles,
the specimen must be kept in the confinement of
the soil throughout the test. Using the sheet
metal clamp with the geotextile glued between the
metal sheets fulfills this purpose and yields uni-
form straining across the width of the geotextile.
3) The uniform raining device developed in the this
study appears to be a good approach for placing
granular soil uniformly in a soil bin.
4) The Hall generator probe-magnet system can measure
the movements of the embedded geotextile along its
length with an accuracy of + 0.01 inch.
5) Upon application of a load increment, the dis-
placement of the geotextile is accompanied by a
reduction in the applied load. This difficulty
affects to a slight degree the accuracy of the
test results.


69
6) Test 1, with a sample length of 27 inches, failed
due to yielding of the geotextile; whereas Tests
2, 3, and 4, with sample lengths of 18, 12, 12
inches, respectively, failed in a pullout mode.
7) As a pulling force is applied to the geotextile
specimen, the movement initiates at the clamped-
end and gradually propagates toward the free-end
as the force increases. The deformation of the
geotextile is the largest at the clamped-end and
becomes smaller toward the free-end. The rate of
reduction in deformation increases as the force
increases.
8) By combining the measured deformations with the
in-soil stress-strain relationship of the geotex-
tile, the tensile force distribution in the
geotextile can be readily determined.


BIBLIOGRAPHY
Barsvary, A. K., MacLean, M. D., and Cragg, C. B. H., "Instru-
mented Case Histories of Fabric Reinforced Embankments
over Peat Deposits, Proceedings of the Second Inter-
national Conference on Geotextiles, Las Vegas, Vol. Ill,
1982, pp. 647-652.
Bell, J. R., and Steward, J. E., "Construction and Observation
of Fabric Retained Soil Walls, Proceedings of the Inter-
national Conference on the Use of Fabrics in Geotechnics,
Paris, Vol. 1, 1977, pp. 123-128.
Bell, J. R., Greenway, D. R., and Vischer, W., "Construction
and Analysis of a Fabric Reinforced Low Embankment,"
Proceedings of the International Conference on the use of
Fabrics in Geotechnics, Paris, Vol. 1, 1977, pp. 71-75.
Bell, J. R., Barrette, R. K., and Ruckman, A. C., "Geotextile
Earth Reinforced Retaining Walls Tests," Glenwood Canyon,
Colorado," Presented at the Annual Meeting, Transpor-
tation Research Record, 1983.
Douglas, G. E., "Design and Construction of Fabric Retaining
Walls by New york State," Presented to the Annual Meeting,
Transportation Research Board, 1982.
Earth Manual, Bureau of Reclamation, Department of the
Interior, Second Edition, Denver, Colorado, 1974, 810 pp.
Fowler, J., Haliburton, T. A., and Langan, J. P., "Design and
Construction of Fabric Reinforced Embankment Test Section
at Pinto pass, Mobile, Alabama," Transportation Research
Record No. 749, 1980, pp. 27-33.
Fowler, J., "Design, Construction, and Analysis of Fabric-
Reinforced Embankment Test Section at Pinto Pass, Mobile,
Alabama," Technical Report EL-81-8, USAE Waterways
Experiment Station, Vicksburg, Mississippi, 1981, 238 pp.
Guido, V. A., Biesiadecki, G. L., and Sullivan, M. I.,Bearing
Capacity of a Geotextile Reinforced Foundation," Proc.
11th ISSMFE, San Francisco, Vol. 3, 1985, pp. 1777-1780.


71
Hoechst Fibers Industries, Trevira Catalog, Spartanburg, South
Carolina, 1984.
Holtz, R. D. "Recent Developments in Reinforced Earth."
Proceeding of the Seventh Scandinavian Geotechnic Meeting,
Published by Polyteknisk Forlag, Copenhagen, Denmark,
1975, pp. 281-291.
Iwasaki, K. and Watanabi, S., "Reinforcement of Highway
Embankments in Japan, Proceedings of the Symposium on
Earth Reinforcement, ASCE, Pittsburgh, 1978, pp. 473-500.
Lee, K. L., Adams, B. D., and Vagneron, J. M. J., "Reinforced
Earth Retaining Walls," Journal of the Soil Mechanics and
Foundation Division, ASCE Vol. 99, No. SM10, 1973,
pp. 745-764.
Liu, H. C., Unpublished Report, Department of Civil Engi-
neering, University of Colorado, Denver, 1985.
Maagdenberg, A. C., "Fabrics Below Sand Embankment Over Weak
Soils, Their Technical Specifications, and Their Appli-
cations in a Test Area," Proceedings of the International
Conference on the Use of Fabrics in Geotechnics. Paris,
Vol. 1, 1977, pp. 77-82.
Murray, R. T., "Fabric Reinforcement of Embankments and
Cuttings," Proceedings of the Second International
Conference on Geotextiles, Las Vegas, Nevada, Vol. Ill,
1982, pp. 707-713.
Siel, B., "An Investigation of the Effectiveness of Tensile
Reinforcement in Strengthening an Embankment over Soft
Foundation," Master's Thesis, Department of Civil Engi-
neering, University of Colorado, Denver, 1986.
Symons, I. F., "Reinforced Earth Retaining Walls," Highway and
Road Construction, 1973, pp. 10-14.
Wager, 0., "Stabilitetsforbattrande Spontkonstruktion for
Bankfyllningar," Swedish Geotechnical Institute, Reprint
and Preliminary Report No. 28, Stockholm, 1968, pp. 21-24.
Whitman, R. V., Getzler, Z., and Hoeg, K., "Static Tests upon
Thin Domes Buried in Sand," The Response of Soil to
Dynamic Loading, Report 12, 1962, Massachusetts Institute
of Technology, Cambridge, Massachusetts.


APPENDIX A
PULLOUT FORCE CORRECTION


73
Table A.l : Calculation of Corrected Overburden Pressure
Test No. : 1 2 3 4
q Unit Weight of Soil, r (lb/ft ) : 106.2 107.2 107.1 107.0
Internal Friction Angle of Soil, (degree) : 37 37 37 37
Overburden Pressure, q (psi) : 4.34 4.34 4.34 4.34
Lateral Pressure Coefficient, kQ : (kQ= 1 sin) 0.4 0.4 0.4 0.4
Soil-Geomembrane Friction Angles &SQ (degree) : 18.5 18.5 18.5 18.5
Friction Resistance Between Soil and Geomembrane, f (psi) : (f = q-k.tanSgG ) 0.58 0.58 0.58 0.58
Percent Mobilization of f, m (%) : 95 95 95 95
Corrected overburden Pressure, f* (f* = f*m ) (psi) : 3.88 3.88 3.88 3.88
Initial Length of Metal Clamp Embedded in soil, L (in.) : 4.84 5.15 5.12 5.00
Metal Clamp Width, W (in.) : 20 20 20 20
Soil-Metal Friction Angle, 6sm (de§ree) : 16.5 16.5 16.5 16.5


74
CORRECTED APPLIED FORCES DATA SHEET
Test No. : 1
Sitting Displacement* : 0.03 in.
Applied Force, P (lb) Reduction in Applied Force (lb) Metal Clamp Displ. (in.) Embedded Metal Clamp Length (in.) Embedded Metal Clamp Area, A (in?) Resistant** Force, F (lb) Correct*** Applied Force, P' (lb)
0 0 0.00 4.84 96.8 222.5 -222.5
50 0 0.00 4.84 96.8 222.5 -172.5
100 - 25 0.00 4.84 96.8 222.5 -122.5
150 - 50 0.01 4.83 96.6 222.5 - 72.5
200 - 75 0.04 4.80 96.0 221.0 - 21.0
250 -100 0.06 4.78 95.6 220.0 30.0
300 -100 0.10 4.74 94.8 218.0 82.0
350 -125 0.25 4.59 91.8 211.0 139.0
400 -125 0.34 4.50 90.0 207.0 193.0
450 -150 0.42 4.42 88.4 203.5 246.5
500 -150 0.49 4.35 87.0 200.0 300.0
550 -200 0.96 3.88 77.6 178.5 371.5
'600 -150 0.97 3.87 77.4 178.0 422.0
650 -200 1.13 3.71 74.2 170.5 479.5
700 -200 1.58 3.26 65.2 150.0 550.0
750 -225 1.79 3.05 61.0 140.5 609.5
800 -250 2.43 2.41 48.2 111.0 689.0
850 -300 3.17 1.67 33.4 77.0 773.0
775 -200 3.99 0.85 17.0 39.0 736.0
700 -150 4.21 0.63 12.6 29.0 671.0
* : The displacement occurs at P1 0
** : F = 2Af**tan<5
*** : ?' = P F SM


75
CORRECTED APPLIED FORCES DATA SHEET
Test No. : ________2 Sitting Displacement* : 0.12 jn.
Applied Force, P (lb) Reduction in Applied Force (lb) Metal Clamp Displ. (in.) Embedded Metal Clamp Length (in.) Embedded Metal Clamp Area, A (in?) Resistant** Force, F (lb) Correct*** Applied Force, P' (lb)
0 0 0.00 5.15 103.0 237.0 -237.0
50 0 0.00 5.15 103.0 237.0 -187.0
100 0 0.01 5.14 1,02.8 236.5 -136.5
150 - 25 0.04 5.11 102.2 235.0 - 85.0
200 - 25 0.08 5.07 . 101.4 233.0 - 33.0
250 - 25 0.13 5.02 100.4 231.0 - 19.0
300 - 50 0.19 4.96 99.2 228.0 72.0
350 - 50 0.25 4.90 98.0 225.5 124.5
400 - 75 0.32 4.83 96.6 222.0 178.0
450 -100 0.38 4.77 95.4 219.5 230.5
500 -100 0.45 i 4.70 94.0 216.0 284.0
550 -150 0.56 4.59 91.8 211.0 339.0
600 -100 0.59 4.56 91.2 210.0 390.0
650 -125 0.72 4.43 88.6 204.0 446.0
700 -150 0.86 4.29 85.8 197.5 502.5
750 -200 1.06 4.09 81.8 188.0 562.0
800 -200 1.35 3.80 76.0 175.0 625.0
850 -250 1.58 3.57 71.4 164.0 686.0
900 -225 1.83 3.32 66.4 153.0 747.0
950 -275 2.20 2.95 59.0 135.5 814.5
1000 -200 2.51 2.64 52.8 121.5 878.5
1050 -300 2.91 2.24 44.8 103.0 947.0
950 -250 3.81 1.34 26.8 61.5 888.5
850 -200 4.66 0.49 9.8 22.5 827.5
* : The displacement occurs at P' 0
** : F 2A*f**tan6
*** : P> P F SM


76
CORRECTED APPLIED FORCES DATA SHEET
Test No. : 3
Sitting Displacement* : 0-10 in.
Applied Force, P (lb) Reduction in Applied Force (lb) Metal Clamp Displ. (in.) Embedded Metal Clamp Length (in.) Embedded Metal Clamp Area, A (in?) Resistant** Force, F (lb) Correct*** Applied Force, P' (lb)
0 0 0.00 5.12 102.4 235.5 -235.5
50 0 o.'oo 5.12 102.4 235.5 -185.5
100 0 0.01 5.11 102.2 235.0 -135.0
150 0 0.03 5.09 101.8 234.0 - 84.0
200 0 0.05 5.07 101.4 233.0 - 33.0
250 0 0.10 5.02 100.4 231.0 - 19.0
300 0 0.16 4.96 99.2 228.0 72.0
350 0 0.21 4.91 98.2 226.0 124.0
400 - 25 0.28 4.84 96.8 222.5 177.5
450 - 50 0.36 4.76 95.0 218.5 231.5
500 - 50 0.44 4.68 93.6 215.0 285.0
550 - 75 0.53 4.59 91.8 211.0 339.0
600 -100 0.64 4.48 89.6 206.0 394.0
650 -100 0.77 4.35 87.0 200.0 450.0
700 -100 0.91 4.21 82.4 190.0 510.0
750 -100 1.13 3.99 79.8 183.5 566.5
775 -100 1.47 3.65 73.0 168.0 607.0
750 - 75 1.86 3.26 65.2 150.0 600.0
675 0 2.22 2.90 58.0 133.5 541.5
500 0 2.52 2.60 52.0 120.0 380.0
450 0 2.96 2.16 43.2 99.5 350.5
400 0 3.40 1.72 34.4 79.0 321.0
300 0 3.90 1.22 24.4 56.0 244.0
* : The displacement occurs at P' 0
** : F 2A*f**tan<5
*** . p p p SM


77
CORRECTED APPLIED FORCES DATA SHEET
Test No- : 4
Sitting Displacement* : 0-23 in.
Applied Force, P (lb) Reduction in Applied Force (lb) Metal Clamp Displ (In.) Embedded Metal Clamp Length (in.) Embedded Metal Clamp Area. A (in?) Resistant** Force, F (lb) Correct*** Applied Force, P' (lb)
0 0 0.00 5.00 100.0 230.0 -230.0
50 0 0.00 5.00 100.0 230.0 -180.0
100 0 0.06 4.94 98.8 227.0 -127.0
150 . 0 0.14 4.86 97.2 223.5 - 73.5
200 0 0.21 4.79 95.8 220.5 - 20.5
250 0 0.27 4.73 94.6 217.5 32.5
300 0 0.34 4.66 93.2 214.5 85.5
350 -25 0.41 4.59 91.8 211.0 139.0
400 -25 0.52 4.48 89.6 206.0 194.0
450 -25 0.59 4.41 88.2 203.0 247.0
500 -50 0.70. 4.30 86.0 198.0 302.0
550 -50 0.85 4.15 83.0 191.0 359.0
600 -50 0.99 4.01 80.2 184.5 415.5
650 -50 1.23 3.77 75.4 173.5 476.5
700 -50 1.64 3.36 67.2 154.5 545.5
625 -25 1.98 3.02 60.4 139.0 486.0
550 0 2.43 2.57 51.4 118.0 432.0
450 0 2.95 2.05 41.0 94.5 355.5
350 0 3.60 1.40 28.0 64.5 285.5
* : The displacement occurs at P' 0
** : F 2A*f**tan 6
*** : P' = P F


APPENDIX B
MAGNET MOVEMENTS DATA SHEETS


79
I ARGE BOX PULLOUT TEST DATA SHEET
Test No. : , / Date i 1-16-86)
Applied Force : 0 lb Temperature ; 69 F
Total Movement : _ 0 in. Humiditv : 4-2.5 (%)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement#
Reference Adjacent Magnets# D
Point# d Magnet# 1 r
(in.) (in.) (in.) (in.)
10 0.00 3.07 0.00 0.00
9 3.0 7
3.02 0.00 0.00
. 8 6.0?
3.00 0.00 0.00
i 7.0?
3.01 0.00 0.00
6 12.10
2.96 0.00 0.00
5 15.06
3.03 0.00 0.00
4 18.01
3.01 0.00 0.00
3 21.10
3.02 0,00 0.00
2 24.12
**** 0.00
1

* : The reference point is selected as the initial free-end
position of the geotextile specimen.
** : r = 1 1, (lo= The initial length between the two magnets)
*** : D =Tr
**** ^ Measured by dial gage


80
IARGE BOX PULLOUT TEST DATA SHEET
Test No. : / Date : / IG 36
Applied Force : 50 lb Temperature : £>9 F
Total Movement : _ 0 in. Humiditv : 4-2.5 {%)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement*
Reference Adjacent Magnets* D
Point, d Magnet, 1 r
(in.) (in.) (in.) (in.)
10 0.00 3.0 7 0.00 0.00
9 3.07
3.02 0.00 0.00
.8 0.O4
3.00 0.00 0.00
7
3.01 0.00 0.00
6 12.10
2.90 0.00 0.00
5 IS. Ok
3.03 0.00 0.00
4 (8.0?
3.01 0.00 0.00
3 21.10
3. 02 0.00 o.oo
2 24.12
0.00
1

* : The reference point is selected as the initial free-end i
position of the geotextile specimen.
** : r = 1 10 do= The initial length between the two magnets)
*** : D =£r !
**** : Measured by dial gage


81
1ARGE BOX PUt LOUT TEST DATA SHEET
Test No. : / Date : / / b 8 b
Applied Force : _ 10 0 lb Temperature : bl F |
Total Movement : . 0 in. Humidity : H-2.5 (%i
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement*
Reference Adjacent Magnets* D
Point* d Magnet* 1 r
(in.) (in.) (in.) (in.)
10 0.00 3.07 0. 00 0. 00
9 3.07
3.02 0. 00 0.00 ;
8 6.0?
3.00 0.00 0.00
7
3.oi .0.00 0.00
6 iz.10
2.1b 0. 00 0. 00
5 15. Ob
3,03 0. 00 0.00
4 18.01
3.01 0. 00 0.00
3 Z(.10
3.02 0.00 0.00
2 2I+. IZ
**** 0.00
1
'
* : The reference point 1s selected as the initial free-end
position of the geotextile specimen.
** : r = 1 lo (lo = The initial length between the two magnets)
*** : D =Sr
**** : Measured by dial gage


82
I ARGE BOX PULLOUT TEST DATA SHEET
Test No. : .... / Date : / 1G 8 6
Applied Force : _ 150 lb Temperature s F
Total Movement : 0.01 in. Humiditv : 42 5 (*)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement,
Reference Adjacent Magnets, D
Point, d Magnet, 1 r
(in.) (in.) (in.) (in.)
10 0.00 5.0& 0.00 0.00
9 3. Olo
3.01 o.oo 0.00
8 <6. o 7
0.00 o.oo
7 tf.Ob
3.00 o.oo 0.00
6 IZ.O&,
3.00 0.00 0. 00
5 IS. 05
2.?? 0.00 0.00
4 18.08
3.03 0.00 o.oo
3 Zl.09
3.01 0.00 0.00.
2 24.11
0.01 **** 0.01
l

* : The reference point 1s selected as the initial free-end
position of the geotextile specimen.
** : r = 1 To (lo = The Initial length between the two magnets)
*** : D =Tr
**** : Measured by dial gage


83
1 ARGE BOX PULLOUT TEST DATA SHEET
Test No. i .. . / nate / |6 36
Applied Force : 2 00 lb Temperature : 69 F
Total Movement : , 0.04 in. Humidity : 42.5 (X)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement,
Reference Adjacent Magnets, D
Point, d Magnet, 1 r
(in.) (in.) (in.) (in.)
10 0,00 3.05 0.0-0 0.00
9 3.05
3.00 o.oo 0.00
8 6. OS'
2 0.00 0.0 0
7 7,04
3.00 0.00 o.oo
6 12.04
2 o.oo 0.00
5 IS. 03
3.01 0.00 0.00
4 18.04
3.01 0.00 0.00
3 21,os
2.18 0.00 0.00
2 24.03
0.04 0.04
l

* : The reference point 1s selected as the initial free-end
position of the geotextile specimen.
** ; r = 1 10 do = The initial length between the two magnets)
*** : D =Ir
**** : Measured by dial gage t


84
I ARGF BOX PULLOUT TEST DATA SHEET
Test No. : 1 Date i 1 lb 86
Applied Force : _ 2 SO _ lb Temperature : G9 F
Total Movement : 0.0b in. Humiditv : H-2.5 (%)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement*
Reference Adjacent Magnets, D
Point, d Magnet, 1 r
(in.) (in.) (in.) (in.)
10 0.00 3.016. 0.00 0.00
9 3.06
3.oi 0.00 0.00
.8 6.07
3. 0 1 0.00 0.00
7 ?.06
2.99 0.0 0 0.00
6 12.06
3.00 0.00 0.00
5 is. OS
2.99 0:00 0,00
4 (8.09
3.OH- 0.00 0. 00
3 21.(2
3.03 0.00 0.00
2 24-, (6
JO. 06 , **** 0.0 6
1

* : The reference point 1s selected as the initial free-end
position of the geotextile specimen.
** : r = 1 10 (lc= The initial length between the two magnets)
*** : D =5!r
**** : Measured by dial gage


85
LARGE BOX PULLOUT TEST DATA SHEET
Test No. i 1 Date 1 lG 8G
Applied Force : _ 300 lb Temperature : G4 F
Total Movement : o.to in. Humidity : 42 5 (%)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement,
Reference Adjacent Magnets, D
Point, d Magnet, 1 r
(in.) (in.) (in.) (in.)
10 0.00 5.ob 0.00 0.00
9 3.0b
3.00 o.oo Q.00
8 (d. oG
2.4 7 0.00 0.00
7 9.03
2.18 0.00 0.00
6 IZ.OI
3.00 0.00 0.00
5 15.01
3.03 o.oo 0.00
4 18M
3.03 0.00 . 0. 00
3 21.07
3.08 0.04 0.04.
2 24.15.
0.0b **** 0. lo
l

* : The reference point is selected as the initial fre6-end
position of the geotextile specimen.
** : r.1 1, (10= The initial length between the two magnets)
*** : D =£r
**** : Measured by dial gage


86
LARGE BOX PULLOUT TEST DATA SHEET
Test No. i . / Date i 1-16-86
Applied Force : _ 35 0 lb Temperature : 61 F
Total Movement : 0. 25 i n. Humiditv : 4-2.5 (*)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement,
Reference Adjacent Magnets, D
Point, d Magnet, 1 r
(in.) (in.) (in.) (in.)
10 0.00 . 3.05 0.00 0.00
9 3.05
3.01 0.00 0.00
8 6.06
Z.H7 0.00 0.00 ;
7 1.03
251 0.0 0 o.oo *
6 12.01
3.00 0.00 0.00 :
5 15.01
3.Oil 0.00 . 0.00
4 I8.0(o
3.04* 0.00 0.00
3 21.10
3.(0 0.06 0.0(o
2 Zl.20
0.11 0.25 ****
1

* : The reference point is selected as the initial free-end ;
position of the geotextile specimen.
** : r = 1 10 (lc= The initial length between the two magnets)
*** : D =5!r
**** : Measured by dial gage


87
LARGE BOX PULLOUT TE£L_DA_TA__SHEEJ
Test No. : __________/ Date : / \(o 8G
Applied Force : UOO lb Temperature : £>*? F
Total Movement : 0.3in. Humidity : 42 5______ (%)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between. Movement
Reference Adjacent Magnets* D
Point* d Magnet* 1 r
(in.) (in.) (in.) (in.)
10 0.00 3.0(o 0.00 0.00
9 3.0(o
3.01 0.00 O.oo
8 (o.O~J
3.00 0.00 o.oo
7 %o 7
3.00 o.oo 0.00
6 /2.07
o.oo 0.00 !
5 IS.ob
3.Oil 0.00 0.00
4 18.(0
3.0il 0.00 o.oo
3 21.18
3JI 0.07 0.01
2 24.2*?
0.27 **** 0.34-
1

* : The reference point 1s selected as the initial free-end
position of the geotextile specimen.
** : r = 1 10 (lo= The initial length between the two magnets)
*** : D =£r
**** : Measured by dial gage I


88
I ARGE BOX PULLOUT TEST DATA SHEET
Test No. : . / Date ; / 16 3 6
Applied Force : _ 450 lb Temperature : £>9 F
Total Movement : 0.42 in. Humidity : 4-2 5 (%)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement,
Reference Adjacent Magnets, D
Point, d Magnet, 1 r
(in.) (in.) (in.) (in.)
10 0.00 3. ob 0.00 0.00
9 3. Ob
2.98 0.00 0.00
8 b.04
3.00 0.00 0.00
7 9.04
2.17 0.00 0.00
6 12.01
3.00 0.00 0.00
5 15.01
3.03 0.00 o.oo
4 18.04
3.07 0.03 0.03
3 21. II
3.08 o.o4 0.07
2 24.19
a 0.35 **** 0.42
1

* : The reference point 1s selected as the initial free-end
position of the geotextile specimen.
** : r = 1 10 (1= The initial length between the two magnets)
*** : D =2r
**** : Measured by dial gage


89
LARGE BOX PULLOUT TEST DATA SHEET
Test No. : , / Hat.fi / J6 36
Applied Force : 500 lb Temperature : F
Total Movement : . 0.47 _ In. Humidity : 4-2.5 (%)
Magnet Distance* Length Movement** Cumulative***
No. From Between Between Movement,
Reference Adjacent Magnets, D
Point, d Magnet, 1 r
(in.) (in.) (in.) (in.)
10 0.00 3. OS 0. 00 0.00
9 3.05
2.71 0.00 0.00
. 8 £>.04
2.11 0.00 0.00
7 7-05
2.77 0.00 0.00
6 12.02
3.01 0.00 0.00
5 IS. 03
3.04 0.00 0.00
4 18.07
3. It 0.07 0.0 7
3 21.18
3.18 0.14 0.21
2 24-.3l>
0.28 **** 0.41
l

* : The reference point 1s selected as the initial free-end
position of the geotextile specimen.
** : r = 1 10 (lo= The initial length between the two magnets)
*** : D =£r
**** : Measured by dial gage


Full Text

PAGE 1

INVESTIGATING SOIL-GEOTEXTILE INTERACTION MECHANISM by Cheng-Kuang Su B.s., Chung-Yang Christian University, 1980 A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirements for the degree of Master of Science Department of Civil Engineering 1986

PAGE 2

This thesis for the Master of Science degree by Cheng-Kuang Su has been approved for the Department of Civil Engineering by 1 ftfB(,

PAGE 3

Su, Cheng Kuang (M.S., Civil Engineering) Investigating Soil-Geotextile Interaction Mechanism Thesis directed by Associate Professor Tzong H. Wu Soil is inherently strong in compression, but weak in tension. The concept of reinforcing an earth fill by incorporating materials which possess a much higher tensile strength than soil and the capability of bonding with soil through friction has recently begun to gain popularity in the United States. Among various materials which have been used as reinforcement, woven and non-woven fabrics (ASTM: "geotextile"), have demonstrated great potential in such applications as embankments over soft ground, earth-retaining walls, foundation mats, and contaminant dikes. In order to investigate the soil-geotextile interaction mechanism, a test was designed in which the geotextile is stressed in tension and is confined in soil. The soil bin is 48 inches by 24 inches in plane and 57 inches high. In the test, a large-size geotextile is embedded in the soil and incremental pulling forces are imposed on a sheet metal. clamp which secures the geotextile specimen along its width. The displacement at the end of the geotextile where the load is applied as well as the displacements along the length of the geotextile were measured. A new procedure for placing the backfill was devised to ensure uniform density in the soil bin. One important aspect of the_ test is that the geotextile must be kept in the confinement of soil throughout the test.

PAGE 4

iv This is necessary in order to measure the displacement at the end of the geotextile where the load is applied, to facilitate control of the applied forces, and to avoid breakage of geotextile specimen as it becomes exposed to the air Displacement patterns of four tests, conducted at an approximately constant soil density, were evaluated to examine the soil-geotextile interaction mechanism for the imposed loading condition. It is to be noted that the tests also provide invaluable controlled test data for verification of numerical models, which, upon establishing their reliability, can be used to investigate the soil-geotextile interaction mechanism in geotextile-reinforced earth structures.

PAGE 5

ACKNOWLEDGEMENTS The study described herein was performed under the supervision of Professor Tzong H. Wu. I am grateful for his support and encouragement throughout my academic and research program. Gratitude is also extended to James Crofter for providing numerous fruitful suggestions in the design of the test equipment in this research. Further special thanks are extended to Barry Siel and Hsing-Cheng Liu for providing their test data and to Hsien-Hsiang Chiang and Victor C. C. Yang for their help in preparation of this thesis. This research work was sponsored by the National Science Foundation and their support is gratefully acknowledged.

PAGE 6

CONTENTS CHAPTER PAGE 1. INTRODUCTION 1 1.1 Problem Statement 1 1.2 Study Objective 3 1.3 Method of Study 4 2. TEST APPARATUS AND INSTRUMENTATION 5 2.1 Description of Test Apparatus 6 2.1.1 Pullout Test Setup 6 2.2.2 Pullout Force Application Setup 6 2.2.3 Surcharge Load Application Setup 11 2.2.4 Soil Placement Device 11 2.3 Instrumentation and Meas')lrement 16 3. LARGE BOX PULLOUT TEST 26 3.1 Material Properties 26 3.1.1 Soil Index Properties 26 3.1.2 Geotextile Properties 26 3.1.3 Frictional Properties 29 3.2 Sample Preparation 29 3.2.1 Small-Scale Raining Device Trial Tests 29 3.2.2 Sample Preparation Procedures 32

PAGE 7

vii CHAPTER PAGE 4. TEST RESULTS AND DISCUSSION OF RESULTS 38 4.1 Applied Loads Versus the Clamped-End Movements . . . . 40 4.2 Applied Loads Versus Movement Along the Geotextiles . . . . 47 4.3 Applied Loads Versus Deformation Along the Geotextiles . . . . . 52 4.4 Tensile Force Distribution Along the Geotextiles 57 5. SUMMARY AND CONCLUSIONS 67 5.1 Summary 67 5.2 Conclusions 68 BIBLIOGRAPHY 70 APPENDIX A. PULLOUT FORCE CORRECTION 72 B. MAGNET MOVEMENTS DATA SHEETS 78

PAGE 8

TABLE 3.1 3.2 4.1 LIST OF TABLES Properties of Trevira 1127 (Trevira Results of Small-Scale Raining Tests Large Pullout Tests PAGE 28 33 39

PAGE 9

FIGURE 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 LIST OF FIGURES Large Pullout Test Setup (a) Plan View (b) Side View Pullout Test Setup Soil Bin for Large Pullout Test Loading Frame and Hydraulic Jack Used for Supplying Load . . . . Exploded View of Sheet Metal Clamp (a) Top View (b) Side View Wooden Panels for Surcharge Load Application Uniform Raining Device Soil Leveling Device 2.9 Pullout Force-Clamp Displacement Measurement Setup 2.10 Hall Generator Probe Setup 2.11 Magnet Movements Tracing Device 2.12 Placement of Outer Tube Above Geotextile 2.13 Magnet Response Recorded by X-Y Recorder 2.14 Electronic Monitoring Device 2.15 X-Y Recorder for Recording Magnetic Field 2.16 Digital Multimeter 3.1 Grain Size Distribution 3.2 Methods for Showering Sand 3.3 Small-Scale Raining Device PAGE 7 8 9 10 12 13 14 15 17 18 19 20 21 22 23 25 27 30 31

PAGE 10

FIGURE 3.4 3.5 4.1 4.2 4.3 4.4 4.5 X PAGE Placement of Magnets on Geotextile Surface 34 The Application of Leveling Device 36 (a) Geotextile Specimen Failure, Test 1 41 (b) Geotextile Specimen Failure, Test 2 41 (c) Geotextile Specimen Failure, Test 3 42 (d) Geotextile Specimen Failure, Test 4 42 (a) Applied Load Versus Clamped-End Movement, Test 1 43 (b) Applied Load Versus Clamped-End Movement, Test 2 44 (c) Applied Load Versus Clamped-End Movement, Test 3 45 (d) Applied Load Versus Clamped-End Movement, Test 4 46 (a) Applied Load Versus Cumulative Displacements Along the Length of Geotextile, Test 1 (b) Applied Load Versus Cumulative Displacements 48 Along the Length of Geotextile, Test 2 49 (c) Applied Load Versus Cumulative Displacements Along the Length of Geotextile, Test 3 50 (d) Applied Load Versus Cumulative Displacements Along the Length of Geotextile, Test 4 51 (a) Applied Load Versus Deformations Between Magnet Stations, Test 1 (b) Applied Load Versus Deformations Between 53 Magnet Stations, Test 2 54 (c) Applied Load Versus Deformations Between Magnet Stations, Test 3 55 (d) Applied Load Versus Deformations Between Magnet Stations, Test 4 56 (a) Deformation Along the Geotextile, Test 1 58

PAGE 11

xi FIGURE PAGE (b) Deformation Along the Geotextile, Test 2 59 (c) Deformation Along the Geotextile, Test 3 60 (d) Deformation Along the Geotextile, Test 4 61 4.6 The Strain Distribution Along the Length of Geotextile in Test 3 for 450 lb Applied Load 62 4.7 (a) Load-Deformation of the Geotextile Tested in the Confinement of soil 64 (b) The In-Soil Stress-Strain Relationship of the Geotextile . 65 4.8 The Force Distribution in the Geotextile for the Applied Load of 450 lb, Test 3 66

PAGE 12

CHAPTER 1 INTRODUCTION 1.1 Problem Statement Soil is inherently strong in compression, but weak in tension. The concept of reinforcing an earth fill by incorporating materials which possess a much higher tensile strength than soil, and the capacity to bond with soil through friction has been utilized quite extensively in Europe, but only recently has the concept begun to gain popularity in the United States. To date, over 5,000 reinforced earth projects have been completed worldwide and they have repeatedly demonstrated superior structural performance, ease and speed of construction, and low costs compared with alternatives in such applications as embankments over soft ground, earth retaining walls, bridge abutments, contaminant dikes, foundation mats, and bulk storage and handling facilities. Both raw materials and manufactured products have been used for earth reinforcement. The best-known earth-reinforcing technique, primarily applied to retaining walls, was developed in France by H. Vidal, and most research heretofore has concentrated on this technique. In the Vidal technique, thin strips of aluminum or steel are placed horizontally in layers. behind a relatively thin concrete or metal "facing," and then

PAGE 13

2 the wall is backfilled in layers with soil. Symons (1973), in an excellent review of research in both France and the United States on the Vidal technique, pointed out a major problem concerning the method the long-term durability of the metallic reinforce-ment. The usual practice, at least in the U.S. is to increase the thickness of metal strips to allow for corrosion (Lee, et al., 1973). However, as with other buried metallic structures such as steel piles, culverts, etc. corrosion rates are highly unpredictable, and it is this uncertainty that makes the Vidal technique less attractive for permanent construction. One viable alternative reinforcing technique is to use woven and nonwoven fabric materials (ASTM : "geotextile") as the reinforcing element. This technique has been applied to embankments over soft foundation (Wager, 1968; Holtz, 1975; Bell, et al., 1977; Maagdenberg, 1977; Fowler and Haliburton, 1980; Fowler, 1981; Barsvary, et al., 1982), retaining walls (Bell and Steward, 1977; Douglas, 1982; Bell, et al., 1983), slope reinforcement (Iwasaki Andwatanabe, 1978; Murray, 1981 and 1982), and bearing capacity improvement of shallow foundations (Guido, et al., 1985). In general, geotextiles are more economical, more easily handled and constructed, and stronger in resisting corrosion and bacterial action than many traditional materials including metals. Moreover, when geotextiles are used as reinforcement, they also serve many other functions such as separation, drainage, and filtration.

PAGE 14

3 Geotextile-reinforced earth structures, however, suffer from a major disadvantage --there is a total lack of understanding as to the reinforcing mechanism. As a result, the design procedures are very empirical and not based on sound engineering research. 1.2 Study Objective The objective of this study is to establish controlled test data for investigation of the soil-geotextile interaction mechanism of geotextile-reinforced earth structures. The interaction mechanism of geotextile-reinforced earth structures is complicated. As a general rule, when a geotextile-reinforced earth mass deforms under applied loads, the geotextile will be subjected to tension provided that there is adequate frictional resistance between the geotextile and soiL As a result, not only will the stresses in the soil mass be redistributed into a more favorable state, the geotextile will react along the surrounding soil, increasing its effective confinement and, hence its stiffness. The extent of the stress redistribution depends on the relative stiffness of the geotextile and the soil, which are both nonlinear in nature, as well as the loading geometry of the geotextile-reinforced earth structures. In order to investigate the soil-geotextile interaction mechanism of different applications of geotextile reinforcement under various conditions, it is essential to develop a numerical model which can realistically and reliably analyze the problem.

PAGE 15

4 The purpose of this study is to provide controlled test data for validation of the analytical model. The test results will also give engineers insight into the soil-geotex-tile interaction mechanism under the test conditions. 1.3 Method of study Laboratory pullout test is a test which many research-ers consider an adequate representation of the real phenomenon that occurs in reinforced earth structures and gives values of soil-reinforcement friction coefficient used for design pur-poses. In the pullout test, a geotextile specimen is embedded in the soil which is confined in a box and is subjected to an overburden pressure. Incremental pullout forces are imposed on one end of. the geotextile specimen so that the geotextile is subject to tension. Relative movement between the soil and geotextile will occur as the geotextile itself deforms and/or the frictional resistance is mobilized. In this study, a large scale pullout test was designed and constructed. The soil bin is 48 inches by 24 inches in plane and 57 inches high. A new procedure for placing the soil was devised to ensure uniform density in the soil bin. A total of four tests were conducted. The displacement at the f end of the geotextile specimen where the load is applied as well as the displacements along the length of the geotextile were measured.

PAGE 16

CHAPTER 2 TEST APPARATUS AND INSTRUMENTATION In this study, a large pullout test apparatus was designed and manufactured. The displacements along the length of the geotextile were measured. The geotextile was confined in soil prepared at a constant density. The soil was subject to a constant vertical load. Since the geotextile must be kept in the confinement of the soil throughout the test, one end the geotextile specimen was glued between a steel sheet metal clamp which is partially embedded in the soil. This prevented unrestrained stretching of the geotextile as it comes out of the pullout box and ensured uniform straining along the width of the geotextile. An electronic monitoring system including a Hall generator probe, a X-Y recorder and a digital multimeter was used to measure displacements of the geotextile. This was accomplished by measuring movements of magnets which were glued at 1.5 to 3 inches intervals along the length of the geotextile surface. The measurement was made by inserting a Hall generator probe with a magnetic sensor into a glass tube which was embedded in the soil immediately above the center I line of the -geotextile. The movements of the magnets were

PAGE 17

6 recorded after each pullout force increment was applied to the geotextile. 2.1 Description of Test Apparatus 2.1.1 Pullout Test Setup The pullout test setup consisted of a steel angle reinforced plywood box and a set of steel tube loading frames with a hydraulic jack reacting against the box to apply pullout forces. The pullout test setup is shown in Figures 2.1 and 2.2. As depicted in Figure 2. 3, the pullout box was constructed from 0.75 inch thick plywood panels on three sides, and on one side by a 0. 75 inch thick acrylic sheet to allow for visual observation of the box interior. The box is 57 inches high with 48 inches by 24 inches in plane. The sides and bottom of the box were secured by using 0.25 inch thick steel angle sections. The four sides of the wall were reinforced by cross-ties at two levels with 0.5 inch diameter steel bars. In order t'o minimize the side wall friction between the box and soil, the interior wall surfaces were lined with a layer of 1/16 inch thick smooth surface geomembrane. 2.2.2 Pullout Force Application Setup A steel tul;>e loading frame with hydraulic jack was designed and built as shown in Figure 2.4. The equipment assembly consisted of a 10 ton capacity hydraulic jack using

PAGE 18

24" L I I Figure 2.1 48" (a) Plan View Surcharge(b) Side View Large Pullout Test Setup (a) Plan View (b) Side View 7 Geotext ile Sheet Metal Clamp Soil Geotextile Sheet Metal

PAGE 19

8 . ... -"' ....... . Figure 2.2 Pullout Test Setup

PAGE 20

Steel Angle Secti ens -.------.. Slot Figure 2.3 Soil Bin for Large Pullout Test 9 Plywood Steel Bar Acrylic Grass "Steel Angle Sections

PAGE 21

. Figure 2.4 Loading Frame and Hydraulic Jack Used for Supplying Load 10

PAGE 22

11 the steel frame to react against the pullout box for application of pulling forces. The connection between the pulling mechanism and the sheet metal clamp was designed to allow for free rotation in the horizontal plane. The arrangement of the connection is illustrated in Figure 2.5. 2.2.3 Surcharge Load Application Setup Dead load was used to supply overburden pressure over the geotextile. The dead load consisted of 36 inch height of sand in the soil bin and 24 sand bags which were placed on wooden panels lying on top of the soil. Figure 2.6 shows the arrangement of the wooden panels. 2.2.4 Soil Placement Device In an attempt to place the sand in the pullout box at an uniform density, a "uniform raining" device shown in Figure 2.7 was devised. The device is a rectangular bin fitting the inside dimension of the pullout box. There are a screen and a two-piece door attached to the bottom of the bin. The door can be opened by releasing cables which are mounted above the soil bin. Detailed procedure of its application is given in Chapter 3. In addition, a leveling device was designed to level the top of the sand prior to placing the geotextile in the pullout box. The leveling device, shown in Figure 2.8, is made of a leveling blade attached to two parallel supporting columns which are hung on a steel tube crossing the top of the

PAGE 23

Sheet Metal Geotextile (a) Top View Sheet Metal Geotextile (b) Side View 12 Steel Plate Free Rotation Connector Steel Plate Free Rotation Connector Figure 2.5 Exposed View of Sheet Metal Clamp (a) Top View (b) Side View

PAGE 24

13 (a) (c) Wooden Lid 47" '/;::/" Figure 2.6: Wooden Panels for Surcharge Load Application

PAGE 25

14 Figure 2.7 Uniform Raining Device

PAGE 26

15 A Figure 2.8 Soil Leveling Device

PAGE 27

16 pullout box. Chapter 3. Procedure for its use is also described in 2.3 Instrumentation and Measurement A dynamometer was used to determine applied pullout forces. The maximum capacity of the dynamometer is 8,000 lb with 50 lb in a division. The 50 lb loading increment was employed for the test. After each load increment was applied, the displacement of the sheet metal clamp was measured by using a dial gage with 0.001 inch an inch accuracy (Figure 2.9). The movements along the length of the geotextile were measured by a Hall generator probe-magnet system. The magnets of 0.06 inch thickness and 1/16 inch diameter were glued along the centerline of the geotextile surface at an interval of 1.5 to 3 inches. The Hall generator probe was housed in a 0.312 inch diameter inner tube (Figure 2.10 and Figure 2.11). For tracing the magnet movements, the probe is inserted into the pullout box through a 0.405 in diameter outer tube, which was placed immediately above the magnets during soil placement (Figure 2 .12). The Hall generator probe responds to a magnetic field in a very sensitive manner. Figure 2.13 shows the response of the probe. to a series of magnets in the form of sine waves. The sine waves were generated by an electronic monitoring device (Figure 2.14) and recorded by a X-Y recorder (Figure 2.15). In the plots, X-axis represents the distance whereas Y-axis record the intensity of the magnetic field. The location of a magnet is at which the Y-axis plot reaches a

PAGE 28

= . : l . Figure 2.9 Pullout Force-Clamp Displacement Measurement Setup 17

PAGE 29

---------_... __ Input Current Pair Hall Voltage Pai.r Figure 2.10 Hall Generator Probe Setup O .uter Tube (to guide inner tube movement) Inner Tube (to house the hall generator 1-' 00

PAGE 30

19 Figure 2.11 Magnet Movements Tracing Device

PAGE 31

20 Figure 2.12 Placement of Outer Tube Above Geotextile

PAGE 32

21 Figure z .u : Magnet Response Recorded by X-Y Recorder

PAGE 33

22 ,-' I : I .. ... .. -... -.. ... -, . -1 r ,.. a a -1 -cr'-r:-::1 .. Figure 2.14 : Electronic Monitoring Device

PAGE 34

23 Figure 2.15 X.-Y Recorder Recording Magnetic Field

PAGE 35

24 maximum (e.g., points A, B, C, and D in Figure 2.13). In order to determine more precisely the movements of the magnets, a digital multimeter was used (Figure 2.16). When the Hall generator probe is directly above a magnet, as indicated by the X-Y recorder, the digital number on the multimeter indicates the distance of the probe movement. The accuracy of the measurement is 0.01 inch.

PAGE 36

25 Figure 2.16 Digital Multimeter

PAGE 37

CHAPTER 3 LARGE BOX PULLOUT TEST 3.1 Material Properties 3.1.1 Soil Index Properties The soil used in this study was a uniform Ottawa sand. The grain size distribution curve of. the sand is shown in Figure 3 .1. The uniformity coefficient of the sand is 1.43. The sand has subrounded grain shape and the specific gravity is 2. 65. The minimum and maximum dry density were determined by Liu (1985) in accordance. with the procedure given in Appendix E-12 on "Relative Density of Cohesionless Soil" of the earth manual (2nd Edition, 1974) as: Maximum Density = Minimum Density = 112.19 pcf 97.52 pcf In the study, the soil is prepared at a density of 107 pc;.f. Results of the triaxial compression tests indicated that the angle of internal friction is 37 degree. 3.1.2 Geotextile Properties The geotextile used in the test is a 100% polyester continuous spun needle punched fabric (Trevira 1127). Table 3.1 shows the. properties of the geotextile given by the manufacturer. The geotextile specimens used in the tests

PAGE 38

27 Gravel Sand Coarse to Fine Silt Clay medium U.S. standard sieve sizes I I 0 0 0 0 0 0 -or .... -or ... N 0 0 0 0 0 0 z z z z z z 100 1 I I I I I rr-. I I I I I \ I I I I I I I I I II I I I I !I I I I I I l I I I I I I I I I 80 ... Q) 60 c: -c: I I I I : 'l I I I I I I II I I I I I I I I I I I I I Ill u .... Q) 0. 40 I I I 'I I l II I I II I i I I I I I I' I I I I I I d I ,, I I I I I I r I I I I I I 'I I I 'I I I I I I I !1 I 20 I I I 1 T II I I I I ... li I j_ I ..l I 1 I I 0 en .,., -o 0 o-.,., N 0 ... "": .,. N ,.. 0 0 cc -or o ci 0 0 .,. ci ci ci ci ci ci Grain diameter, mm "Figure 3.1 Grain Size Distribution (Liu, 1985)

PAGE 39

28 Table Properties of Trevira 1127 (Trevira Catalog, 1984) 1 2 3 4 2 Fabric Weight (oz/yd ) Thickness (Mils) (ASTM D-1777) Grab Strength (lb, MD/CD) (ASTM D-1682) Grab Elongation (%, MD/CP) (ASTM D-1682) 8 125 260/225 85/95 MD = Machine Direction CD = Cross Machine Direction

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29 were 18 inches wide with three different lengths: 27, 18, and 12 inches. 3.1.3 Frictional Properties The friction angle between the soil and sheet metal, which was the material used for the metal clamp in the pullout test, was determined to be 16. 5 degrees. The friction angle between the soil and the that was used to line the interior of the pullout box was found to be equal to 18 5 degrees. Both were obtained from direct shear tests with a soil density of 107 pcf. 3.2 Sample Preparation 3.2.1 Small-Scale Raining Device-Trial Tests From published literature, sand placement in large scale tests has usually been carried out by using showering methods as illustrated in Figure 3.2. These showering methods, however, were not used in this study, because it was believed that a uniform method would give better results. In order to gain some experience with the uniform raining a small-scale test apparatus, shown in Figure 3. 3, was first constructed. The apparatus consisted of two containers with one fitting inside of the other. The outside container has interior dimensions of 1 ft by 1 ft by 1 ft. The inside container has a screen attached to its bottom for sand to rain through. The screen was identical to the one used for the uniform raining device (Chapter 2). A series of

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f . . . .. . . . . . I I I I I I I I I .. . . . . II "' I I ' : r. .. .. ... ... 6 I "l . ... ::.:.:. .... :: >( . .. ;. ::: ,1:, ... : ....... I I I of I ott 0 0::', :.: ::0;: \ \? 0 ... :'. :. : .. : . .: . .. = .. I II I. II I 0 :I I lo I I Ill I lo IIIII METHOD A Central pour creating sloped surface. (loose sdnd) .. I I I . . .... . I I o o I .. . . ... "' l .. . :P .. L:..:..-J .. ..... : ..... :. : ({::.; AJ . .. .. .. ... .... : :.< ::: ... ... .. .,:: .: ...... .. :-:.:. I t I o ... METHOD B ''combined funnels" pouring, creating o flat surface (dense sand ) Figure 3.2 : Methods for Showering Sand (Whitman, et al., 1962) ... . .. . .. .. I ,'t . . .. . .. I I I I .. . ... ./' :. ; .. .. :. : ,t I I I ... METHOD C Pouring through muzzle pipe, creating a flat surface (dense sand) I w 0

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31 .. """Figure 3.3 Small-Scale Raining Device

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32 tests was conducted with the small-scale raining device. The results are presented in Table 3. 2. It is seen that the device provi4es a consistent means for placing the sand uniformly in a container. With a rain height of 15 inches the soil density is approximately 107 pcf. 3.2.2 Sample Preparation Procedures The procedures for sample preparation are described in the following: 1) trim the geotextile specimen to the selected size; 2) glue magnets to the surface of the geotextile at pre-determined intervals of 3 inches along the centerline of the geotextile (Figure 3 4) leave overnight for the glue to set; 3) cover the magnets with scotch tape to provide a even surface; 4) attach the "uniform raining" device on the top of the pullout box to allow for a rain height of 15 inches above the sand surface; 5) place a predetermined amount of sand (to form approximately 2. 5 in. soil layers in the box) in the uniform raining device and level the surface in the device; 6) release cables to open up the doors at the bottom of the uniform raining device and allow the sand to "rain" uniformly in the pullout box;

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33 Table 3.2 Results of Small-Scale Raining Tests Test Height of Rate of Unit No. Free Fall Flow Weight (in.) (ft3imin.) (pcf) ------------------------------------------------------1 1 0.73 102.6 2 1 0.75 102.5 3 1 0.74 102.5 4 15 0.75 107.3 5 15 0.74 107.2. ------------------------------------------------------

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34 Figure 3.4 Placement of Magnets on Geotextile Surface

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35 7) raise the uniform raining device to a height of 15 inches above the new soil surface; 8) place the same amount of sand in the uniform raining device and allow the sand to "rain" in the box in the same manner as step 6; 9) repeat steps 5 through 8 until the soil surface reaches the height of the front slot; 10) use additional sand (preweighed) to rain through the four edges of the uniform raining device to obtain a more level surface; 11) remove the uniform raining device and use the leveling device (see Chapter 2) to ensure a level surface (Figure 3.5); 12) place the geotextile specimen on the top of sand surface and line up the specimen with the centerline of the sheet metal clamp; 13) rest the glass tube immediately above the magnets; 14) repeat steps 5 through 8 to place an additional 20 inches of sand above the geotextile specimen; 15) remove the uniform raining device and level the top layer of the soil surface; 16) measure the height of the specimen and calculate the density of the sand; 17) place a sheet of plastic on the top of the specimen for calculations of the unit weight after the test; 18) place additional sand to fill the pullout box;

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36 Figure 3.5 The Application of Leveling Device

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;.: 37 19) place 24 sand bags on the plywood panel resting on the sand surface to simulate the overburden pressure. In the study, the total load above the geotextile amounts to an equivalent overburden pressure of 4.34 psi.

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CHAPTER 4 TEST RESULTS AND DISCUSSION OF RESULTS In this study, four geotextile samples of three different lengths with a constant width were tested. The soil was. prepared at a density of approximately 107 pcf. The geotextile was subject to 4.34 psi of overburden. A constant increment of 50 lb pulling force was applied to the geotextile. Measurement of the movements of the geotextile along its length was taken as each load increment was applied. The test condition of the four pullout tests is summarized in Table 4.1. All the tests were conducted until a failure condition developed. The failure condition is defined herein as the limiting condition at which significant movement of the geotextile occurred abruptly and continuously. As the failure load was reached, the load would drop rapidly and it would not be possible to maintain the loading level. Except for Test 1, failure condition developed in the form of "pullout", i.e., the failure load was reached after the frictional resistance at the soil-geotextile interface had been fully mobilized. In these cases, movement at the freeend initiated prior to the failure load was applied. In Test 1, due to the length of the specimen, the free-end did

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39 Table 4.1 : Large Pullout Tests Test Geotextile Geotextile Soil* Overburden No. Specimen Specimen Density Above the Length Width Geotextile (in.) (in.) (pcf) (psi) ---------------------------------------------------------1 27 18 106.2 4.34 2 18 18 107.2 4.34 3 12 18 107.1 4.34 4 12 18 107.0 4.34 The soil density was determined prior to application of overburden; at the end of the tests, the densities were found to increase approximately by 0.5 pcf.

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40 not move throughout the test. Failure in Test 1 was a result of yielding of the geotextile. The configuration of the specimens upon the completion of the tests are shown in Figure 4.1. 4.1 Applied Loads Versus the Clamped-end Movements The loading history and the relationships between applied pulling forces and the clamped-end movements of the four tests are depicted in Figure 4.2. The left side of the figure shows the loading history. The loads were applied at a constant increment of 50 lb. As the movement of the geotextile occurred in response to a load increment, it was accompanied by a reduction in the force exerted by the hydraulic jack. The reductions are shown in the figure as dashed lines. In Tests 1 and 2, the reductions were fairly significant. This was partially because there was a faulty valve in the hydraulic jack. The problem was corrected before conducting Tests 3 and 4. The right side of Figure 4. 2 shows the applied load versus clamped-end movement. As may be expected, the load-deformation characteristics were approximately the same for all four tests in the early portion of the loading history; Tests 3 and 4, with a shorter geotextile specimen, reached the failure condition at smaller loads than Tests 1 and 2. It is of interest to note that Test 1, with a longer geotextile specimen, failed at a smaller load than Test 2. This is due to the fact that Test 1 did not fail in the same

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41 Figure 4.1 (a) Geotextile Specimen After Failure, Test l Figure 4.1 (b) Geotextile Specimen After Failure, Test 2

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42 Figure 4.1 (c) Geotextile Specimen After Failure, Test 3 ..:,;.... . ..... --, _ '-.i .. ,. .... , .. I.' . t .i . .. ... 1 Figure 4.1 (d) Geotextile Specimen After Failure, Test 4

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,/ I I I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I 1 I 1 I I I I : : I I 1 I I I 1 I I I I I I I I I I I I I I I 1,000 -.0 ...... .._, 500 I I 10 I I / I I I I I I I I I 5 0 1 2 3 Load Increment No. Clamped-End Movement, D Figure 4.2 (a) Applied Load Versus Clamped-End Movement, Test 1 43 4

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I I I I I 1 I I 1 I I 1 I ,J I I I I I I I I I I I I I I I I I I I f I I I I I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I 15 10 I I I I I I I I 5 I I I 1,000 0 3 Load Increment Clamped-End Movement, D (in.) Figure 4.2 (b) Applied Load Versus Clamped-End Tes. t 2 44 4

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45 1,000 [}-+ p -.0 D ..... -P-t .. Cll 0 Ql ..... 0. 0. l < j I W f I I I I I f 1 I 1 I f I I I I I I I I I I I I I I /1 I ( I I I I :t 1 0 3 4 Load Increment No. Clamped-End Movement, D (in.) Figure 4.2 (c) Applied Load Versus Clomped-End Movement, Test 3

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I I I I .' i I I I I I I I 1,000 .500 p -.J D Load Increment No. Clamped-End Moyement, 0 (in.) Figure 4.2 (d) Applied Load Versus Clamped-End Movement, Test 4 46

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47 mode as the other tests. In Test 1, yielding of the geotextile dictated the failure condition as the free-end did not move throughout the tests. This observation indicated a very important design consideration -yielding (rupture) of gao textiles can be a governing factor in design of geotextile.., reinforced earth structures. Tests 3 and 4 were conducted with presumably identical conditions. The difference in the test results (of approximately 50 lb load ) was attributed primarily to the difficulty in lining up the pulling mechanism on a level plane with the geotextile specimen at the beginning of the tests. It should be noted that since the applied forces were partially resisted by the friction between the metal clamp and the confining soil, the forces applied to the geotextile had to be corrected by subtracting the frictional forces over the embedded area of the metal clamp from the corresponding applied forces. The corrections are summarized in Appendix A. All the applied loads reported in this chapter are corrected loads unless specified otherwise. 4.2 Applied Load Versus Movements Along the Geotextiles Figure 4.3 shows the relationships between the loads applied to the clamped-end of the geotextile and the cumulative movements along the length of the geotextile. The cumulative movements in the geotextile were measured by the Hall generator probe-magnet system at selected points. The movements represent the compound effect of

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........ ..-t '-J .. Q) e Q) (.)
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3 2 ....... c:: .. c:: QJ 8 QJ C) n:l 0. en ..... 0 1 Figure 4.3 (b) 49 T Station 1 7 6 5 4 3 2 1 18" p l 181'--+1 A 1a I 2 2a 3 4 5 9 500 1,000 Applied Load, P (lb) Applied Loads Versus Cumulative Displacements Along the Length of Geotextile, Test 2 No.

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50 3 T 18" 54321. p 2 1 -121'_,j c -1::::1 .. Station No. c CLI a 1 CLI (J ell ...-! 0. en la 1::::1 1 2 2a 3 3a 4, 4a, 5 0 500 1,000 Applied Load, P (lb) Figure 4.3 (c) Applied Loads Versus Cumulative Displacements Along the Length of Geotextile, Test 3

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3 2 '-' ... Q) a Q) C) ell ...-1 c.. en 1 0 0 Figure 4.3 (d) f 18" i 5 4 3 2 1 .. p 500 Station No. 1 1a 2 2a 3 3a 4 4a, 5 Applied Load, P (lb) 1,000 Applied Loads Versus Cumulative Displacements Along the Length of Geotextile, Test 4 51

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52 stretching of the geotextile and the sliding against the soil. Ten magnet stations were used in Test 1. Tests 2, 3, and 4 used 9 magnets. The layout of the magnet stations are depicted in Figure 4.3. The shaded area in Figure 4.3 (a) illustrates the portion of geotextile that remains stationary in Test 1. Measurements of magnet movement of the four tests are presented in Appendix B. As can be expected, the movement of the geotextile began at the clamped-end where the load was applied and gradually propagated toward the free-end as the load increased. 4.3 Applied Loads Versus Deformations Along the Geotextile Geotextile is a "deformable" material. When a tension load increment is applied to one end of an embedded geotextile specimen, the movement of the geotextile is due entirely to stretching of the geotextile itself until a large enough load is reached so that sliding of the entire specimen against the soil begins to take place. Figure 4.4 illustrates the deformation (stretching) along the length of the geotextile in response to applied loads for the four tests. It is shown that the deformation initiates at the clamped-end and propagated toward the free-end as the load increased. The darkened area of Test 1 specimen indicated the region that remained stationary in the test. The shaded area of Tests 2, 3, and 4 specimens shows the portion of the geotextile in which deformation has not developed before sliding of the specimens occurs.

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-..c -i:l< A "=' t1l 0 ,...J "Q Ill ..-1 c. c. < 53 Magnet Stations 5-6 4-5 3-4 2-3 1-2 750 500 8 7 6 5 4 3 2 1 0 p 250 No Movement between Soil and Geotextile 0 :;'igure 4.4 (a) 0.5 1.0 Deformation (in.) Applied Loads Versus Deformations Between Magnet Stations, Test l

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-,Q -"' "tl t1S 0 ...J "tl QJ c.. c.. < 1,000 4-5 750 500 250 54 3-4 2-3 Magnet Stations 1-2 0 No Deformation before Sliding p 0 0.5 Figure 4.4 (b) 1.0 Deformation (in.) Applied Loads Versus Deformations Between Magnet Stations, Test 2

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3-4 """' 500 ..c .-l ......, .. "C co 0 ...:I "C QJ .-l Q. Q. < 250 0 0 Figure 4.4 (c) 2-3 Magnet Stations 1-2 p No .Deformation before Sliding 0.5 1.0 Deformation (in.) Applied Loads Versus Deformations Between Magnet Stations, Test 3 55

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Magnet Stations 4-4a 3-4 2-3 1-2 0 0 Figure 4.4 (d) 0.5 1.0 Deformation (in.) Applied Loads Versus Deformations Between Magnet Stations, Test 4 56

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57 The load-deformation curves ar.e seen to have a slight degree of fluctuation especially near the clamped-end where the imposed loading history illustrated in Figure 4.2. Results of Tests 3 and 4, which were conducted in presumably the same conditions, were nearly identical when shifting the load by a 50 lb difference. This is consistent with the observations discussed in Section 4.1. Figure 4.5 depicts the deformations along the geotex-tiles at different load levels for the four tests. As a general rule, it is seen that the deformation along the geotextile reduced toward the free-end. The rate of reduction increases as the load level increases. 4.4 Tensile Force Distribution Along the Geotextile The tensile force distribution in the geotextile specimens at a given applied load can be determined from the strain distribution along the length of the geotextile and the load-deformation relationship of the geotextile under the same test conditions as the pullout tests. The following shows how to obtain the force distribution using results of Test 3 as an example. The strain distribution along the length of the geotextile in Test 3 for an applied load of 450 lb at the clamped-end is shown in Figure 4.6. The strain distribution was computed by dividing the deformation (stretching) of the geotextile between any two magnet stations (Figure 4.5 (c)) by initial distance between the magnet stations.

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58 Applied Load, P (lb) 1.0 8 7 6 5 4 3 2 p 689 . c: ...._, 610 c: 0 J.J C1l sso No Movement between e f-1 Soil and Geotextile 0 311 ..... ell 479 Q 422 0.5 246 300. 193. 139 82. 0.0 30 0 2 3 4 5 6 7 8 Magnet Station No. Figure 4.5 (a) Deformations Along the Geotextile, Test 1

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59 Applied Load, P (lb) 1.0 947 -. c:: 878 "'"l -c:: 814 p 0 "'"l Cl! 747 a .,.. 0 686 (11 625 No Deformation before Sliding 0.5 562 502 446 390 339 284 230 178 124 72 0.0 1 3 4 5 6 7 Magnet Station No. Figure 4.5 (b) Deformations Along the Geotextile, Test 2

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60 Applied Load, P (lb) p 607 0.5 566 No Deformation t: Sliding 510 .._, t: 450 0 394 ,j..J 111 339 e ,... 0 \j.j 28! <1.1 23 177 124 0.0 72 1 3 4 5 Magnet Station No. Figure 4.5 (c) Deformations Along the Geotextile, Test 3

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61 4 3 2 r p Applied Load, p ( lb) 0.5 545 No Deformation = 476 ..-I before Sliding .._, 415 c: 0 359 ..-I .u ctt s ,... 0 302 11-4 QJ 247 194 139 85 32 0.0 1 2 3 4 5 Magnet Station No. Figure 4.5 (d) Deformations Along the Geotextile, Test 4

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20 0 1 Figure 4.6 62 2 3 Magnet Station No. The Strain Distribution Along the Length of the Geotextile in Test 3 for 450 lb Applied Load

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63 Figure 4.7 (a) shows the curve of the geotextile tested in the confinement of soil. The curve was obtained by employing a specially designed apparatus with the same soil type, the same geotextile, the same soil density, and the same overburden pressure as Test 3 in this study. The test apparatus was developed by Siel (1986). The in-soil stress-strain relationship of the geotextile, which was deduced from Figure 4.7 (a), is illustrated in Figure 4. 7 (b). By combining Figures 4. 6 and 4. 7 (b), the force distribution in Test 3 for the applied load of 450 lb could be determined as shown in Figure 4.8.

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300 ......... 200 .0 .-I '-J p., A "" ell 0 ,...J QJ .-I 0. 0. < 100 0 o.o Figure 4.7 (a) 0.3 0.6 0.9 1.2 Deformation (in.) The Load-Deformation of the Geotextile Tested in the Confinement of Soil 64

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750 Figure 4.7 (b) 80 Strain (%) The In-Soil Stress-Strain Relationship of the Geotextile 65

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Q) CJ ,..., 0 s;... 600 400 200 0 -Figure 4.8 _l I _j I 2 3 4 5 Magnet Station No. The Force Distribution in the Geotextile for the Applied Load of 450 lb, Test 3 66

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CHAPTER 5 SUMMARY AND CONCLUSION 5.1 Summary In this study, exl?erimental tests were performed to investigate soii-geotextile interaction behavior in the pullout test. A large pullout test apparatus was designed and manufactured for this study. The soil bin is 48 inches by 24 inches in plane and 57 inches high, constructed with 0.75 inch thick plywood by using steel angle sections. to secure the sides and bottom. There is a 0.5 inch wide slot on the front side of the bin to attach the geotextile to a loading mechanism. In the tests, a large size non-woven geotextile was embedded in a granular soil of a constant uniform density and incremental pulling forces were imposed on a sheet metal clamp which secured the geotextile specimen along its width. The displacement at the clamped-end of the geotextile as well as the displacements along the length of the geotextile were measured by a Hall generator probe-magnet system. A total of four tests were performed. The tests varied in specimen length and were conducted until a "failure condition" was reached. The study should provide. invaluable

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68 controlled test data for verification of numerical modeling of soil-geotextile interaction. 5.2 Conclusions The findings and conclusions of this study are summarized in the following: 1) The large test setup devised in this study can be used to conduct test satisfactorily and gives consistent test results. 2) In order to conduct pullout test of geotextiles, the specimen must be kept in the confinement of the soil throughout the test. Using the sheet metal clamp with the geotextile glued between the metal sheets fulfills this purpose and yields uniform straining across the width of the geotextile. 3) The uniform raining device developed in the this study appears to be a good approach for placing granular soil uniformly in a soil bin. 4) The Hall generator probe-magnet system can measure the movements of the embedded geotextile along its length with an accuracy of 0.01 inch. 5) Upon application of a load increment, the displacement of the geotextile is accompanied by a reduction in the applied load. This difficulty affects to a slight degree the accuracy of the test results.

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69 6) Test 1, with a sample length of 27 inches, failed due to yielding of the geotextile; whereas Tests 2, 3, and 4, with sample lengths of 18, 12, 12 inches, respectively, failed in a pullout mode. 7) As a pulling force is applied to the geotextile specimen, the movement initiates at the clampedend and gradually propagates toward the free-end as the force increases. The deformation of the geotextile is the largest at the clamped-end and becomes smaller toward the free-end. The rate of reduction in deformation increases as the force increases. 8) By combining the measured deformations with the in-soil stress-strain relationship of the geotextile, the tensile force distribution in the geotextile can be readily determined.

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BIBLIOGRAPHY Barsvary, A. MacLean, M. D., and Cragg, C. B. H., "Instru mented Case Histories of Fabric Reinforced Embankments over Peat Deposits," Proceedings of the Second International Conference on Geotextiles, Las Vegas, Vol. III, 1982, pp. 647-652. Bell, J. R., and Steward, J. E., "Construction and Observation of Fabric Retained Soil Walls," Proceedings of the International Conference on the Use of Fabrics in Geotechnics, Paris, Vol. 1, 1977, pp. 123-128. Bell, J. R., Greenway, D. R., and Vischer, w., "Construction and Analysis of a Fabric Reinforced Low Embankment," Proceedings of the International Conference on the use of Fabrics in Geotechnics, Paris, Vol. 1, 1977, pp. 71-75. Bell, J. R., Barrette, R. K., and Ruckman, A. c., "Geotextile Earth Reinforced Retaining Walls Tests," Glenwood Canyon, Colorado," Presented at the. Annual Meeting, Transportation Research Record, 1983. Douglas, G. E., "Design and Construction of Fabric Retaining Walls by New york State," Presented to the Annual Meeting, Transportation Research Board, 1982. Earth Manual, Bureau of Reclamation, Department of the Interior, Second Edition, Denver, Colorado, 1974, 810 pp. Fowler, J., Haliburton, T. A., and Langan, J. P., "Design and Construction of Fabric Reinforced Embankment Test Section at Pinto pass, Mobile, Alabama," Transportation Research Record No. 749, 1980, pp. 27-33. Fowler, J., "Design, Construction, and Analysis of FabricReinforced Embankment Test Section at Pinto Pass, Mobile, Alabama," Technical Report EL-81-8, USAE Waterways Experiment Station, Vicksburg, Mississippi, 1981, 238 pp. Guido, v. A., Biesiadecki, G. L., and Sullivan, M. r.,"Bearing Capacity of a Geotextile Reinforced Foundation," Proc. 11th ISSMFE, San Francisco, Vol. 3, 1985, pp.

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71 Hoechst Fibers Industries, Trevira Catalog, Spartanburg, South Carolina, 1984. Hal tz, R. D., "Recent Developments in Reinforced Earth." Proceeding of the Seventh Scandinavian Geotechnic Meeting, Published by Polyteknisk Forlag, Copenhagen, Denmark, 1975, PP 281-291. Iwasaki, K. and Watanabi, S., "Reinforcement of Highway Embankments in Japan," Proceedings of the Symposium on Earth Reinforcement, ASCE, Pittsburgh, 1978, pp. 473-500. Lee, K. L., Adams, B. D., and Vagneron, J. M. J., "Reinforced Earth Retaining Walls," Journal of the Soil Mechanics and Foundation Division, ASCE Vol. 99, No. SM10, 1973, PP 745-764. Liu, H. c., Unpublished Report, Department of Civil Engineering, University of Colorado, Denver, 1985. Maagdenberg, A. c., "Fabrics Below Sand Embankment Over Weak Soils, Their Technical Specifications, and Their Applications in a Test Area," Proceedings of the International Conference on the Use of Fabrics in Geotechnics. Paris, Vol. 1, 1977, PP 77-82. Murray, R. T., "Fabric Reinforcement of Embankments and Cuttings," Proceedings of the Second International Conference on Geotextiles, Las Vegas, Nevada, Vol. III, 1982, PP 707-713. Siel, B., "An Investigation of the Effectiveness of Tensile Reinforcement in Strengthening an Embankment over Soft Foundation," Master's Thesis, Department of Civil Engineering, University of Colorado, Denver, 1986. Symons, I. F., "Reinforced Earth Retaining Walls," Highway and Road Construction, 1973, pp. 10-14. Wager, o., "Stabilitetsforbattrande Spontkonstruktion for Bankfyllningar," Swedish Geotechnical Institute, Reprint and Preliminary Report No. 28, Stockholm, 1968, pp. 21-24._ Whitman, R. v., Getzler, z., and Hoeg, K., "Static Tests upon Thin Domes Buried in Sand," The Response of Soil to Dynamic Loading, Report 12, 1962, Massachusetts Institute of Technology, Cambridge, Massachusetts.

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APPENDIX A PULLOUT FORCE CORRECTION

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73 Table A.l : Calculation of Corrected Overburden Pressure -------------------------------------------------------------Test No. 1 2 3 4 ------------------------------------------------------------Unit Weight of Soil, r (lb/ft3 ) : 106.2 107.2 107.1 107.0 Internal Friction Angle of Soil, (degree) 37 37 37 37 Overburden Pressure, q (psi) 4.34 4.34 4.34 4.34 Lateral Pressure Coefficient, k0 0.4 (k = 1 0 0.4 0.4 0.4 Soil-Geomembrane Friction Angle, OSG (degree) 18.5 18.5 18.5 18.5 Friction Resistance Between Soil and Geomembrane, f (psi) 0.58 o.58 o.58 o.58 ( f = q k tan oSG ) Percent Mobilization of f, m (%) : 95 95 95 95 Corrected overburden Pressure, f* (f* = fm ) (psi) 3.88 3.88 3.88 3.88 Initial Length of Metal Clamp Embedded in soil, L (in.) 4.84 5.15 5.12 5.00 Metal Clamp Width, W (in.) 20 20 20 20 Soil-Metal Friction Angle, oSM (degree) 16.5 16.5 16.5 16.5 ------------------------------------------------------------

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CORRECTED APPLIED FORCES DATA SHEET Test No. 1 Sitting Displacement* Applied Reduction Metal Embedded Embedded Force, in Clamp Metal Metal p Applied Dis pl. Clamp Clamp Force Length Area, A (lb) (!b) (in.) (in.) (in f) -0 0 0.00 4.84 96.8 50 0 0.00 4.84 96.8 100 25 0.00 4.84 96.8 150 50 0.01 4.83 96.6 200 -75 0.04 4.80 96.0 250 -100 0.06 4.78 95.6 300 -100 0.10 4.74 94.8 350 -125 0.25 4.59 91.8 400 -125 0.34 4.50 90.0 450 -150 0.42 4.42 88.4 500 -150 0.49 4.35 87.0 550 -200 0.96 3.88 77.6 '600 -150 0.97 3.87 77.4 650 -200 1.13 3. 71 74.2 700 -200 1.58 3.26 65.2 750 -225 1. 79 3.05 61.0 800 -250 2.43 2.41 48.2 850 -300 3.17 1.67 33.4 775 -200 3.99 0.85 17.0 700 -150 4.21 0.63 12.6 : The displacement occurs at P' 0 ** F = 2Af*tano *** P' = p -F SM Resistant** Force, F (lb) 222.5 222.5 222.5 222.5 221.0 220.0 218.0 211.0 207.0 203.5 200.0 178.5 178.0 170.5 150.0 140.5 111.0 77.0 39.0 29.0 74 0.03 in. Correct*** Applied Force, P' (lb) -222.5 -172.5 -122.5 -72.5 21.0 30.0 82.0 139.0 193.0 246.5 300.0 371.5 422.0 479.5 550.0 609.5 689.0 773.0 736.0 671.0

PAGE 86

75 CORRECTED APPLIED FORCES DATA SHEET Test No. 2 Sitting Displacement* 0.12 in. Applied Reduction Metal Embedded Embedded Resistant** Correct*** Force, in Clamp Metal Metai Force, F Applied p Applied Dis pl. Clamp Clamp Force, Force Length Area, A P' (1b) (1b) (in.) (in.) (in f) (1b) (1b) 0 0 0.00 5.15 103.0 237.0 -237.0 50 0 o:oo 5.15 103.0 237.0 -187.0 100 0 0.01 5.14 1,02.8 236.5 -136.5 150 -25 0.04 5.11 102.2 235.0 85.0 200. -25 0.08 5.07 101.4 233.0 33.0 250 -25 0.13 5.02 100.4 231.0 19.0 300 50 0.19 4.96 99.2 228.0 72.0 350 50 0.25 4.90 98.0 225.5 124.5 400 75 0.32 4.83 96.6 222.0 178.0 450 -100 0.38 :4.77 95.4 219.5 230.5 500 -100 0.45 '4. 70 94.0 216.0 284.0 550 -150 0.56 4.59 91.8 211.0 339.0 600 -100 0.59 4.56 91.2 210.0 390.0 650 -125 o. 72 4.43 88.6 204.0 446.0 700 -150 0.86 4.29 85.8 197.5 502.5 750 -200 1.06 4.09 81.8 188.0 562.0 BOO -200 1.35 3.80 76.0 175.0 625.0 850 -250 1.58 3.57 71.4 164.0 686.0 900 -225 1.83 3.32 66.4 153.0 747.0 950 -275 2.20 2.95 59.0 135.5 814.5 1000 -200 2.51 2.64 52.8 121.5 878.5 1050 -300 2.91 2.24 44.8 103.0 947.0 950 -250 3.81 1. 34 26.8 61.5 888. 5 850 -200 4.66 0.49 9.8 22.5 827.5 The displacement occurs at P' 0 F 2Af*tanO P' p -F SM

PAGE 87

76 CORRECTED APPLIED FORCES DATA SHEET Test No. 3 Sitting Displacement* 0.10 in. Applied Reduction Metal Embedded Embedded Resistant** Correct*** Force, in Clamp Metal Metal Force, F Applied p Applied Displ. Clamp Clamp Force, Force Length Area, A P' (lb) (lb) (in.) (in.) (in f) {lb) (lb) 0 0 o.oo 5.12 102.4 235.5 -235.5 50 0 0.00 5.12 102.4 235.5 -185.5 100 0 0.01 5.11 102.2 235.0 -135.0 150 0 0.03 5.09 101.8 234.0 84.0 200 0 0.05 5.07 101.4 233.0 33.0 250 0 0.10 5.02 100.4 231.0 19.0 300 0 0.16 4.96 99.2 228.0 72.0 350 0 0.21 4.91 98.2 226.0 124.0 400 25 0.28 4.84 96.8 222.5 177.5 450 50 0.36 4.76 95.0 218.5 231.5 500 50 0.44 4.68 93.6 215.0 285.0 550 -75 0.53 4.59 91.8 211.0 339.0 600 -100 0.64 4.48 89.6 206.0 394.0 650 -100 0.77 4.35 87.0 200.0 450.0 700 -100 0.91 4.21 82.4 190.0 510.0 750 -100 1.13 3.99 79.8 183.5 566.5 775 -100 1.47 3.65 73.0 168.0 607.0 750 -75 1.86 3.26 65.2 150.0 600.0 675 0 2.22 2.90 58.0 133.5 541.5 500 0 2.52 2.60 52.0 120.0 380.0 450 0 2.96 2.16 43.2 99.5 350.5 400 0 3.40 1. 72 34.4 79.0 321.0 300 0 3.90 1.22 24.4 56.0 244.0 : The displacement occurs at P' 0 ** F 2A f tan cS *** P' p -F SM

PAGE 88

CORRECTED APPLIED FORCES DATA SHEET Test No. 4 Sitting Displacement* Applied Reduction Metal Embedded Embedded Resistant** Force, in Clamp Metal Metal p Applied Dis pl. Clamp Clamp Force Length Area, {lb) (lb) (in.) (in.) (in f) -0 0 0.00 5.00 100.0 50 0 0.00 5.00 100.0 100 0 0.06 4.94 98.8 150 0 0.14 4.86 97.2 200 0 0.21 4.79 95.8 250 0 0.27 4.73 94.6 300 0 0.34 4.66 93.2 350 -25 0.41 4.59 91.8 400 -25 0.52 4.48 89.6 450 -25 O.S9 4.41 88.2 500 -so 0.70 4.30 86.0 5SO -so 0.85 4.15 83.0 600 -50 0.99 4.01 80.2 6SO -so 1.23 3. 77 75.4 700 -so 1. 64 3.36 67.2 625 -25 1. 98 3.02 60.4 550 0 2.43 2.57 51.4 450 0 2.95 2.0S 41.0 350 0 3.60 1.40 28.0 : The displacement occurs at P' 0 ** F s 2Af*tan6 *** P' c p -F SM Force, F A (lb) 230.0 230.0 227.0 223.5 220.5 217.5 214.5 211.0 206.0 203.0 198.0 191.0 184.5 173.5 154.5 139.0 118.0 94.5 64.S 77 0.23 in. Correct*** Applied Force, P' (lb) -230.0 -180.0 -127.0 73.5 20.5 32.5 85.5 139.0 194.0 247.0 302.0 3S9.0 415.5 476;5 545.5 486.0 432.0 355.5 285.5

PAGE 89

APPENDIX B MAGNET MOVEMENTS DATA SHEETS

PAGE 90

79 LARGE BOX PULLOUT TEST DATA SHEET Test No. : I Date : l-lb-8b Applied Force 0 lb Temperature F . Total 'Moverr.ent : 0 in. Humidity : 1./-Z. 5 (%) t-1agnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D PQint, d Magnet, 1 r (in.) (in.) (in.) (in.) 10 o.oo 3. 07 0.00 0.00 9 3.07 3 .02 0.00 o. 00 8 b. 0'/ 3.00 0.00 0.00 7 9.0'/ 3.01 0.00 o.oo 6 12. I 0 : 2.9b 0.00 0.00 5 ts. ob tB.o'f 3.03 o.oo 0.00 4 3.0/ 0.00 0.00 3 21. /0 3. 02 o.oo 0,00 2 21./. 12 **** -0.00 1 l : The reference point 1s selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo Clo = The initial length between the two magnets) *** : D **** Measured by dial gage

PAGE 91

80 LARGE BOX PULLOUT TEST DATA SHEET Test No. Date : l-lf1-8b Applied Force 50 lb Temperature bqo F Iota 1 Movement : 0 in. Humidity : 4-2.5 (%) Magnet Distance* Length Movement** Cumulative*** No. 10 9 8 7 6 5 4 3 2 1 : ** *** **** From Between Between Movement, Reference Adjacent Magnets, 0 Point, d Magnet, 1 r (in.) (in.) (in.) (in.) o.oo 3. 07 0,00 0.00 3.07 3.02 0.00 o. 00 b.oq 3.00 0.00 0.00 9.09 3.01 0.00 o.oo 12. I 0 2.9b 0.00 0.00 15.06 {8. 3.03 0,00 0. 00 3.0/ 0.00 0.00 21. I 0 3. 02 0,00 0,00 24.12 **** -0.00 -: I i The reference point 1s selected as the initial free-end 1 position of the geotextile specimen. r = 1 -lo Clo = The initial length between the two magnets) D I Measured by dial gage

PAGE 92

81 LARGE BQX PULLOUT TEST QATA SHEET Test No. : Date : I I b 8 b Applied Force __ lb I' 0 0 Temperature _'0.:......;-,:..-_ F Total Moverrnt : 0 in. Humidity : _.:!..ll-..=Z:...::..::5:___ Magnet Distance* Length Movement** Cumulative*** No. 10 9 8 7 6 5 4 3 2 1 From Between Between Movement, Reference .Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.> (in.) (in.> 0.00 3. 07 0. 00 0.00 3.07 3.02 0. oo o. 00 6.o? c;.o? 3.00 0.00 0. 00 3. ()' .0.00 0.00 /Z.IO 15. Ob 2.CJb 0.00 0.00 /8.09 .3.03 0. 00 0. 00 3.0 I 0. 00 0.00 21. 10 3.02 0.00 o. 00 21./-.12. **** -Q.OO -* : The reference point 1s selected as the initial free-end position of the geotextile specimen : I I I I I I ' ** : r = 1 1o
PAGE 93

82 LARGE BOX PULLOUT TEST DATA SHEET Test No. : Date : I-Ib-8b Ap p 1 i ed Force /50 lb Temperature F Total Movement : o. 0 I in. Humidity : 4-2.5 (%) t-1agnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in. ) 10 o.oo 3.0b 0. 00 0.00 9 3 Ofo 3. o I o.oo 0.00 8 .. .07 Cf. ofo 2.99 0.00 0.00 7 /2.0fo 3.00 0.00 0.00 6 3.00 0.00. 0,00 5 15.05 /8.08 2. 99 0,00 0,00 4 Z/.09 3.03 0.00 0 .00 3 3.01 0.00 0.00 2 21./.. I f **** 0. o I 0. 0 I 1 -* : The reference point 1s selected as the initial free-end position of the geotextile specimen. ** r = 1 lo Clo. = The in it i a 1 1 ength between the two magnets) *** D **** Measured by dial gage

PAGE 94

83 LARGE BOX PULLOUT TEST QATA SHEET Test No. : Date : IJf,-8b Applied Force 200 lb Temperature G'fo F Total Moven;ent : 0. 0/.1.. in. Humidity : li-Z. 5 (%) tagnet Distance* Length Movement** Cumulative*** No. 10 9 8 7 6 5 4 3 2 1 From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.) (in.> (in.) o.oo 3.05 o.o.o 0.00 3.05" 3.00 o.oo 0.00 Cf. OJ./. 2. Cj? 0.00 0, 00 12, Ot/-3.00 0.00 0.00 i 2.99 o.oo 0.00 /5". 03 /8.043. ()( o.oo 0.00 3.0/ 0.00 0.00 Zl. OS 2.(8. 0.00 0.00 2Lf.. 03 **** O.OLJ. 0.01./-* : The reference point 1s selected as the initial freE;-end position of the geotextile specimen. ** : r = 1 1a
PAGE 95

84 LARGE BQX PULLOUT TEST QATA SHEET Test No. Date : ./-ff,-8b Applied Force 25D lb Temperature bqo F Total Movement : o.oh in. Humidity : ll-2.5 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in. > 10 o.oo 3.0b. 0.00 o. 00 9 3.0b 3.0/ 0.00 0. 00 8 b.07 C(.Ob 3.0 I 0.00 0.00 7 2. 9 '1 0.00 0.00 6 3.00 0.00 0.00 5 IS. os 2. 99 oo 0.00 4 18.09 3, 04-0.00 0. 00 3 2/./2 J.03 0. 00 0.00 2 24. tb **** O.Ob 1 -* : The reference point 1s selected as the initial free-end position o{ the geotexti.le ** r = l -lo
PAGE 96

85 LARGE BOX PULLOUT TEST DATA SHEET Test No. Date : l-lb-8b Applied Force 0 300 lb Temperature F Total Moverr.ent : 0.10 in. Humidity : l./-2. 5 (%) Magnet Distance* Length Movement** Cumulative*** No. 10 9 8 7 6 5 4 3 2 1 From Between Between Movement, Reference Adjacent Magnets, 0 Point, d Magnet, l r (in.> (in.) (in. ) o.oo 3.06 0,00 0.00 '3.00 I 3.00 o.oo Q.OO 2.97 0.00 0 00 9.03 2.'18 0.00 0.00 I 2. 0 I 3.00 0,00 0.00 t5. o I .3.03 0.00 o.oo t8.0L/.. I 3.03 0.00. 0. 00 2/.07 3.08 O,Otf., b. 01./-2/..15 **** O.Ob 0. IO -* : The reference point 1s selected as the initial free-end position of the geotextile specimen. ** r : = 1 lo Cla = The initial length between the two magnets) I *** 0 =Lr **** Measured by dial gage

PAGE 97

86 lARGE BOX PULLOUT TEST QATA SHEET Test No. Date : IJb-8b Applied Force .350 b Temperature G'fo F T ota 1 Moverr.ent : 0.25 in. Humidity Li-Z. 5 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 10 0.00 3.05 0.00 o. 00 9 3.05" 3. o I 0.00 0.00 8 6.ob 2. 97 0.00 0.00 : 9.03 7 2. '19 0. 00 0. 00 I I 6 12.02. I 3,00 0.00 0.00 5 /5.02. /8.00 3.0Lf. 0.00 0.00 4 2/.10 3. Ol/-0. 00 0,00 3 Zt/-.20 3.{0 o.ot:, o.ofo 2 **** 0.1'1 0.25 1 -* : The reference point 1s selected as the initial free-end: position of the geotextile specimen. ** : r = 1 -lo Clo = The initial length between the two magnets) *** : 0 **** : Measured by dial gage

PAGE 98

87 LARGE BQX PULLOUT TEST DATA SHEET Test No. : Date : I-lb8b Ap p 1 i ed Force L/.00 lb Temperature GCf0 F Total Moverr.ent 0.34in. Humidity : l./-2.5 {%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between. Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r .(in.) {in.) (in.) {in.> 10 o. 00 3 .0b (), 00 0.00 9 3.06 3. 0/ 0.00 0.00 8 0.07 3.00 0.00 0 .00 7 Cj.07 3.00 0.00 0.00 6 12.07 /fi.ob 2. '1'1 0.00 0.00 5 3. ()Lf.. 0. 00 0.00 4 18. ( 0 3.01./-0.00 0.00 3 21.18 3.11 0.07 0.07 2 21./-. **** 0.27 0.341 -. *:'The reference point 1s as the initial free-end position of the geotextile specimen. ** r = 1 -lo
PAGE 99

LARGE BOX PULLOUT TEST PATA SHEET Test No. . Date : IJb-8b Applied Force f.!. SO lb Temperature : .. f;,Cfo F Total Moverr.ent : 0. f/.2 in. Humidity : li-Z. 5 t-1agnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) ( 1 n.) 10 0.00 3.0b o. 00 0.00 9 3.0b b. OL/. 2/18 o.oo 0.00 8 3.00 0.00 0. 00 7 9.0lf 2.97 0.00 0. 00 6 12. o I 3;00 0.00 0.00 5 15.0 I 3,0'3 0.00 0.00 4 /B. OJ/-3.07 0.0.3 0.03 3 21. I I 3.08 0. OL/. 0.07 2 2#-.J'( **** 0.35 0. LJ.2 1 -* : The reference point 1s selected as the initial free-end position of the geotextile specimen. 88 ** : r = 1 lo
PAGE 100

89 LARGE BOX PULLOUT TEST DATA SHEET Test No. Date : Ilb-8b Applied Force 5'00 lb Temperature F Total Moverr.ent : O.l/-9 in. Humidity : li-Z. 5 (%) Magnet Distance* Length Movement** Cumulative*** No. From Set ween Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) .. ( 1 n.) (in.) (in.) 10 0. 00 3.0S o. 00 0.00 9 3,05 2. Cf9 0.00 0.00 8 b .OJ./-9.03 2. 0 00 0.00 7 2.99 0.00 0. 00 6 /2.02 3.0/ 0,00 0.00 5 15.03 3. Of./-0,00 0.00 4 /8.07 2/.18 3. II 0.01 0 .07 3 3.18 0.14 0.2/ 2 24-.3fo **** 0,28 1 -* : The reference point 1s selected as the initial free-end position of the geotextile specimen. ** r = 1 lo Clo = The in it i a 1 1 ength between the two magnets) *** D =2:r **** Measured by dial gage

PAGE 101

90 LARGE BOX PULLOUT TEST DATA SHEET Test No. Date : 1-Jb-8b Applied Force . 550 lb Temperature F Total Moverr.ent 0.96 in. Humidity : l./-2 5 (%) Magnet Length Movement** cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 10 o.oo 3,05 0, 00 0.00 9 3.05 3.02 0.00 0,00 8 6.07 9.ob 2.?9 0. 00. .0.00 7 3.02 0.00 0.00 6 12.08 2.99 0.00 0.00 I 5 /5.07 3,0b 0.02 0.02 4 !8. /3 3.15 0. II 0.13 3 2/.28 .3.3/ 0.17 0.30 2 21./..s
PAGE 104

93 LARGE BOX PULLOUT TEST PATA SHEET Test No. Date : I-16-8b Applied Force zoo lb Temperature f>'iD F Total Moverr.ent : /.58 in. 4-2.5 (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.) (in.) (in.> 10 0.00 3. o.oo 0.00 9 3.0fa G. OL/.-2.98 o.oo 0.00 8 9.03 2. If? 0. 00 o.oo 7 12.03 3,00 0.00 0.00 6 3.05 0. OL/-0. OL/5 /5.08 3./5 0. J I 0./5 4 1-8.23 3.30 0.2{,. 0./.f./ 3 21.53 2.5. I 'f 3.J./.(o 0. f./.2 0.8.3 2 '**** 0.75 1.58 1 : The reference point 1s selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo Clo = The in it 1 a 1 1 ength between the two magnets) *** D **** : Measured by dial gage

PAGE 105

94 LARGE BQX PULLOUT TEST DATA SHEET Test No. Date : IJf,-8b Applied Force 150 lb Temperature () F Total : /. 79 in. Humidity : li-Z. 5 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in. ) 10 0.00 3.05 0.00 0.00 9 3.05 G.OL/.-2.?9 o,oo 0.00 8 9.02. 2.'/8 o.oo 0. 00 7 ' 3.00 0.00 0.00 6 IZ.o2 3.01/-0.03 0.03 5 IS. Ob 3,17 0.13 0. tb 4 {8;Z3 3.3l/-0.30 O.l/.b 3 21.57 3.51 0 .ll-7 0. '13. 2 25,08 **** -o.Bb I. 79 1 -* : The reference point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo C1o = The 1nit1a1 length between the two magnets) *** D =Lr **** : Measured by dial gage

PAGE 106

95 LARGE BOX PULLOUT TEST DATA SHEET Jest No. Date : I-Jf,-8b Applied Force Boo lb Temperature f>'10 F Total Moverrnt : 2.Lt3 in. Humidity : 4-2.5 (%) Magnet Distance* Length Movement** Cumulative*** No. 10 9 8 7 6 5 4 3 2 1 From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in. ) 0. 00 3.Db 0.00 o. 00 3. ob ..3.02 0. 00 0.00 9 I 1/ 3.02 0. 00 3.01./-0.01./-0. 01./. 12.15 3.12 0./1 0.15 15.27 /8.54 3.27 0.23 0.38 3.L/S O.J./.1 0. 7'1 3.JD O.bb 1.4-5 **** 0, '18 2.1./.3 -* : The reference point 1s selected as the initial free-end position of the geotextile specimen. ** : r = l -lo Clo = The 1 nit i a 1 1 ength between the two magnets) *** D =Z:r **** : Measured by dial gage

PAGE 107

96 LARGE BOX PULLOUT TEST DATA SHEET Test No. : Date : I-Jf,8b Applied Force 8So lb Temperature F Total : 3.(1 in. Humidity : l.i-2. 5 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 10 0.00 3.07 0,00 (), 00 9 3,07 3.0/ 0,00 0.00 8 6.08 3;00 0.00 o.oo 7 9.08 12. rtl-3.06 o,ob. 6 3.21 0,20 0.2b 5 /5. 35" 3./fO 0. 31../-o.bo 4 /8. 75" 3, (:,(:, 0.62 I. 22 3 22.1.././ 3. 7b 0.72 I. 942 26.t1 **** /,23 3.17 1 -* : The reference point 1s selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo Clo = The initial length between the two magnets) D =Lr **** : Measured by dial gage

PAGE 108

97 LARGE BOX PULLOUT TEST DATA SHEET Test No. Date : I-lb-8b Applied Force 77S lb Temperature F Total Moverrnt : in. Humidity : !l-2. 5 (%) fagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, 0 Point, d Magnet, 1 r (in.> (in.> (in.> (in. ) 10 0.00 3.06 3.0b 0, 00 0.00 9 b.07 3.0 ( 0,00. o.oo 8 3.03 o. oi./-0.01./7 Cf, I 0 12.1? 3.07 0.13 6 3.2b 0.25 5 15.1./.5 /8.?5 3.50 0. 1./.b 0,8/.1. 4 22.67 3.72 0.68 1.52 3 2b.JIS 3.78. 0, 742.2b 2 **** .[a 73 3.99 1 : The reference point 1s selected as the initial free-end position of the geotextile specimen. ** : r = 1 -1o Clo = The in it i a 1 1 ength between the two magnets) *** : 0 **** : Measured by dial gage

PAGE 109

98 LARGE BQX PULLOUT TEST DATA SHEET Test No. : Date : I16-Bb Applied Force ]00 lb Temperature F Total Moverr.ent L/.. 2/ in. Humidity : 4-Z. 5 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 10 o.oo 3.08 3.0.8 o.oo o.oo 9 6.08 3.00 0.00 a.oo 8 -'/.{3 3.05 0.05 0.05 7 3. 10 0, ( 0 0.15 6 /2.23 0.28 O.J-/-3 5 15.52 1
PAGE 111

100 LARGE BQX PULlOUT TEST DATA SHEET Test No. 2 Date : I 24 86 Applied Force Temperature : Total Movement : _..;;..s_o __ lb in. Humidity : 40.0 (%) tagnet Distance* Length Movement** Cumulative*H No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, r (in.) (in.) (in.) (in.) 7 0.00 2 'II.J. 0100 0.00 6 2.91./-3.03 0.00 0. 00 5 5/17 2.9/o 0.00 0.00 4 8.C/3 3.03 0.00 0.00 3 II. ?6 13.4-8 /.52 0.00. 0.00 2a 2 I Lf.. ?7 /.I+? o.oo 0.00 /.5'1 o.oo 0.00 la /b.#B **** -0.00 1 -* : The reference pQint is selected as the initial free-end position of the geotextile specimen. ** r = 1 -lo Clo =The initial length between the two magnets). *** D = I:r **** : Measured by dial gage

PAGE 112

101 LARGE BQX PULLOUT TEST DATA SHEET Test No. 2 Date : I 2/.f 86 Applied Force IOO lb Temperature . 68 F Total Movement : 0.0/ in. Humidity : 40.0 (%) Magnet Distance* length Movement** Cumulative**il No. From Between Between Movement, Reference Adjacent Magnets, D Point:, d Magnet, 1 r Cin.) (in. ) (in.) (in.) 7 o.oo 2.'11-to.oo 0.00 6 3.02 o.oo o.oo 5 5.'/b 2/f7 0.00 o.oo 4 8.93 I t. '/5 3.02 0.00 0. 00 3 13.JI.7. /.52, o.oo 0.00 za lll-.97 /.50 2 0.00 0.00 tb.'+7 /.50 0.00 0,00 la **** -0.0 I 0. o I 1 : The refer-ence pQint is selected as the initial free-end position of the geotextile specinen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = **** Measured by dial gage

PAGE 113

102 LARGE BQX PULLOUT TEST PATA SHEET Test No. 2 Date : I 2/.f 86 Applied Force IS 0 lb Temperature 68 F Total MoverrEnt : O. Ol/in. Humidity : 40.0 (%) Magnet No. 7 6 5 4 3 2a 2 la 1 ** *** **** Distance* Length Movement** Cumulative**il From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.> (in.) (in.> o.oo 2.'14o.oo o.oo 2.94-. 5.9b 3.02 o.oo o.oo 2.97 0.00 0.00 8. Cf3 0,00 0.00 (.53 -o.oo o.oo l.5D 0.00 0.00 fJ/-.19 /6. Lf't /,50 o.oo 0.00 **** O.OL.{. 0. OL/. -The refer ence point is selected as the initial free-end position of the geotextile specimen. r = 1 lo
PAGE 114

103 LARGE BQX PULLOUT TEST PAJA SHEET Test No. 2 Date : I 2 LJ. 8b Applied Force 200 lb Temperature 68" F Total Moverrent : o.oB in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.) (in.) (in.) 7 o.oo 2. 94-(9; 00 o. 00 6 2.'/L/-3.03 o.oo OL 00 5 5.97 2,qlo o.oo o.oo 4 8.Cf3 3.03 o.oo 0. 0 0 3 I /. Yb J3,L+7 l15/ o.oo 0.00 Za [1-/...Cf? I.SZ 0.00 o.oo 2 I /.5"0 ().00 0. 0 () la a **** 0.08 0,0 1 -* : The refer ence point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo (lo =The initial length betwe.en the two magnets) *** D = **** : Measured by dial gage

PAGE 115

104 LARGE BOX PULLOUT TEST DATA SHEET Test No. 2 Date : I 2/.f 86 Applied Force 250 lb Temperature . 68 F Total Movernent : 0./3 in. Humidity : 40.0 (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, l r (in. ) (in.> (in.) (in.) 7 0,00 2 ,q L/o. 00 6 3.03 .. 0.00 0.00 5 S.Cf1 -2.'f.b 0. 00 0.00 4 8.93 I I. '/7 z. ol/o.oo 0,00 3 .J3 .48 ().00 0.00 2a L.ol 0.00 O.DO 2 ltt,q't ljS2 0 02. 0.02 la tb.S/ **** -o. I I o. 13 1 : The reference point is selected as the initial free-end position of the geotextile specimen. ** r = l -lo Clo = The initial length between the two magnets) *** : D = **** Measured by dial gage

PAGE 116

105 LARGE BQX PULLOUT TEST DATA SHEET Test No. : Date : I 24--86 Applied Force 3 00 lb Temperature 68 ____ F Total Movement: 0.19 in. Humidity : 40.0 (%) tagnet Distance*' Length Movement** Cumu 1 at i ve*H No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.> (in.) (in.) 7 0.00 2.'11/0. 00 0, 00 6 2. q 1./5.97 3,03 0.00 o.oo 5 8.q3 2. 9(o 0.00 0 00 4 I I. 9 7 3. Ol/-0 .00 0,00 3 I 540.02 o. 02 2a 13.5/ {,SZ 0.02 0. OL/. 2 15.03 {.52 0.02 O.Ob la If. 55 **** -o. t 3 0 .1'1 1 -* : The reference point 1s selected as the initial free-end position of the geotext1le specinen. ** r = 1 -lo Clo =The initial length between the two magnets) *** D = Lr **** Measured by dial gage

PAGE 117

106 LARGE BQX PULLOUT TEST DATA SHEET Test No. 2 Date : I 2/.f-86 Applied Force 350 lb Temperature . 68" F Total Movement : 0.25 in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative**il No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in. ) Cin.) (in.) (in.) 7 0,00 2. 9 4-0.00 0, 00 6 2. 94-3.03 0,00 0.00 5 5.97 2.9b o.oo 0.00 4 8.93 3.0b 0,03 0 03 3 1/.99 /.Sb 0. 01./-0,07 2a 13.52 1.52 0.02 o.o9 2 IS. 0 1.f. /.SL/-0. OL/.. 0 t3 la /b.5S **** 0./2 0.25" 1 -* : The refer ence pQint 1s selected as the initial free-end position of the geotextile specimen. ** : r = 1 lo (lo = The initial length between the two magnets) *** D =Lr **** Measured by dial gage

PAGE 118

107 LARGE BQX PULLOUT TEST PATA SHEET Test No. . 2 Date : I 24-86 Applied Force 4-0o lb Temperature . 68 F Total Movement : ().32 in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative**'* No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 (in. ) (in.) (in.) (in.) 7 0.00 2 .<1 L/. 0 ,00 (), 0 0 6 2. 94-S.Cf 1 3.03 0,00 o.oo 5 8,q3 2.9b 0.00 0, 00 4 3.DS. 0.03 o.o3 3 !1/18 t ,sb o.ot.fo.o7 2a /3. 5/f. 1.52 0,02 o.o1 2 /5. 0/:> o ob 0.15 lb. 62 la **** 0,17 0.32. 1 -* : The refer:ence point 1s selected as the initial free-end position of the geotext1le specimen. ** r = 1 -lo
PAGE 119

108 LABGE BOX PULl OUT TEST DATA SHEET Test No. 2 Date : I 2/.f 86 Applied Force lj_SO lb Temperature 68" F Total Movement : Q.38 in. Humidity : 40.0 <%> Magnet Distance* Length Movement** Cumulative*H No. From Between Between Movement, Reference Adjacent Magnets; D Point, d Magnet, 1 r (in.> (in.> (in.) (in.) 7 0.00 2.93 o. 00 0, oo 6 2.'13 3.02 0.00 0. 00 5/15 5 2.97 0.00 0.00 4 8.92 3 .0b 0 03 0.03 3 1!. 98 { .5L/-0.02 0.05' 2a J3.52 {.sb O.Ob 0 ( ( 2 15.08 /0.65 /.57 0.07 0.18 la **** 0,20 0.38 1 -* The refer ence point is selected as the initial free-end position of the geotextile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = Lr **** Measured by dial gage

PAGE 120

109 LARGE BQX PULLOUT TEST DAJA SHEET Test No. : 2 Date : I 2/.f 86 Applied Force sao lb Temperature 68" F Total MovenEnt : O.JI-5 in. Humidity : 40.0 (%) Magnet No. 7 6 5 4 3 2a 2 la 1 : Distance* Length Movement** Cumulative*** From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.> (.in. ) {in.) 0, 00 2.Cf4-0.00 0. OD 2. Cf4-5/11 3,03 o.oo 0.00 2.9 o.oo 0. DO 8. '13 3.00 0.03 0.03 I I. 99 (.5b O.OL/.. 0. 07 /3.!)5 /,55 0.05 0. /2 15,/0 /.5/ 0.09 0.2/ /6, b{ **** -0. 21/-0.45 -The refer ence point fs selected as the initial free-end position of the geotextile specinen. I ** *** **** r = 1 lo Clo = The initial length between the two magnets) : D = Measured by dial gage

PAGE 121

110 LARGE BOX PUUOUT TEST QATA SHEET Test No. 2 Date : I 2 L/. 86 Applied Force sso lb Temperature 68" F . Total Movement : O.Sb in. Humidity : 40.0 (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 7 (). 0 0 2,qe:, o. 0 0 o. oO 6 2. 3,02 o.oo o. oo 5 5.98 3.00 O,Of o.oLf 4 3. I I o.oo 0./2 3 /2.07 /.58 o.o6 0. {8 2a /3,bS /.5t./. o. o'-1-0.22 2 /5.1 {.5'j o.o9 0.3/ la /6.78 **** 0.25 0".5b 1 : The reference point is selected as the initial fres-end position of the geotextile specimen. ** : r = 1 -lo Clo = The initial length between the two magnets) *** : D = **** : Measured by dial gage

PAGE 122

111 LARGE BQX PULLOUT TEST PATA SHEET Test No. : 2 Date : I 24-8b Applied Force tbO 0 1 b _..;;;._ __ ____ F Temperature : Total Movement : 0.5? in. Humidity : (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) 7 o.oo 2.qlf o;oo 0,00 6 2.94-.3,02 0,00 0,00 5 5.9b 3.00 0. Olf o.ot/4 3 ,09. o.ob o. r o 3 12.0S 1.57 0.05 2a 13.62 {.57 0,07 0.22 2 15.t'( ( b,8L/. t .bs 0,15 .. 0.37 la **** 0.22 0.5
PAGE 123

112 LARGE BOX PULLOUT TEST DATA SHEET Test No. 2 Date : I 2 L/. 86 Applied Force 050 lb Temperature . 68 F Total Moverrent : 0.72 in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, 0 Point, d Magnet, 1 r (in.> (in.) (in.> (in.) 7 0. 00 2. qy.. 0. ov 0, 00 6 2. 9/f 3.01f {).00 0.00 5 s. cr s 3. 00 O.DL/. 0. OL/4 3. '1 $ 3.12 0.08 0.12 3 12.10 2a 13. 6C( 1.5/ 0. OJ 0. It( {.59 0.0 '1 0.28 2 15.28 lb. 9S (.by 0. '7 0. l./-5 la **** 0.2J 0.72 1 : The refer ence point is selected as the initial free-end position of the geotextile specimen. ** r = 1 lo
PAGE 124

113 LARGE BQX PULLOUT TEST DATA SHEET Test No. 2 Date : I 24-8b Applied Force 700 lb Temperature 68 F i o.8b I Total Moverrent : in. Humidity : 40.0 (%) I fagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r Cin.) Cin.> (in.> (in.) 7 0.00 : : 2.9J.f.. 0 00 0.00 6 2.945,q7 3.03 0. 00 0. 00 5 1 3.02 0.06 0. Of:> 4 8.99 I 3. ( 3 0, { 0 0. /h 3 /2.12 I. b2. 0. (0 0.2b 2a /3.74/. b2 0.12 0.38 2 I. 7 I 0. 2/ 0,5'7 la 17.07 **** 0.27 0.86 1 -* : The point is selected as the initial free-end position of the geotexti1e specimen. ** : r = 1 -1o Clo = The in it 1 a 1 1 ength. between the two magnets) *** : D = **** : Measured by dial gage

PAGE 125

114 LARGE BOX PULLOUT TEST QATA SHEET Test No. : z Date : I 21./. 86 Applied Force 750 lb Temperature 68Q F Total : 1.06 in. Humidity : 40.0 (%) Magnet D i Length Movement** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 ,r (in.) (in.) (in.) cin.> 7 {). 0 0 2.CJLf o.oo 0,00 6 2.'14 3, () t.f. : o.oo 0.00 5 5.98 .B. 02 0.0/J O.Ob 4 8.98 l2. 18 3. 18 0.15 0. 2/ 3 I I. b4-0.12 0.33 2a 13.82 I l 05 O.tS o. J./.8 2 15. LJ-7 I /. 7t.f 0. 2J/-0.72 la I 7.21 ****I -0.34 /. o6. 1 I : The refer ence point is selected as the initial free-end .position of the .eotextile specimen. 9 ** : r = 1 lo Cla =The initial length between the two magnets) ***: D =Lr **** : Measured by dial gage

PAGE 126

115 LARGE BQX PULLOUT TEST DATA SHEET Test No. 2 Date : I 24-86 Applied Force 800 lb Temperature . 68 F Total MovenEnt : /,3S in. Humidity : 40.0 (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 7 0, 00 0.00 O(OD 6 2.91f 3.05 0. o I 0. 0 I 5 5.91 3.03 0.07 0.08 4 c;.oz 3.23 0.20 0.28 3 12.25 /. 05 0. 13 0. 4-1 2a /3. /. 7o 0. 20 o. b I 2 15.60 /. 77 0. 2L/o.85 la 17.37 **** 0. 5"0 /.35 1 -* : The reference pQint is selected as the initial free-end position of the geotextile specimen. ** : r = 1 -1o Clo = The in it i a 1 1 ength between the two magnets) *** : D = **** : Measured by dial gage

PAGE 127

116 LARGE BQX PULLOUT TEST PATA SHEET Test No. 2 Date : I ...: 21./.-86 Applied Force 850 lb Temperature 68 F Total Movement : /.58 in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative*H No. From Between ,Between Movement, Reference Adjacent_ Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 7 o.o I 2, 'lS' c9, 0 0 0. 0 I 6 z.q(:;i \ 3. OL/. 0.0/ 0, 02 5 3.06 0. (0 o. rz 4 Cf.tJb 3.2? o. 24-0.36 3 12.33 I Lf.. 02 I. 0.17 0 53 2a /.75 0.25' 0.78 2 : 15,77 J 7, 5b-I .97 I. 07 la **** 0.51 !.58 1 -* : The reference point is selected as the initial free-end position of the geotextile specinen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D **** Measured by dial gage

PAGE 128

. 117 LARGE BQX .PULLOUT TEST DATA SHEET Test No. . 2 Date : I ...; 2/..1. 86 Applied Force 900 lb Temperature 68 F Total MoverrEnt : ..;,83 in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, l r (in.) (in.> (in.) (in.> 7 0,02 2. CJL{-0.00 0, 02 6 2. 'tb' 6.03 3.07 O. O'f 0.06 5 3.08 0. I 2. 0.18 4 9.1 I 3,35 0.32. 0.50 3 12.1.1-b /. 73 0.2/ D. 71 Za /1/-.19 /. 77 0.27 o. 98 2 IS /jfo /, 82 0,32 /.30 la 17.78 **** 0.53 1.83 1. . : The reference point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo Clo = The initial length between the two magnets) *** : D = **** : Measured by dial gage

PAGE 129

118 LARGE BQX PULLOUT TEST DATA SHEET Test No. : 2 Date : I ;,. 24-86 Applied Force lb Temperature 68 F Total Movement : 2.20 in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative*H No. From. Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (iii.) (in.) (in. ) 7 0.0'-/. 2/15 o. o I o, 05 6 3,08 0.05 0. /0 5 b.07 3.13 0.17 0.27 4 9.20 3.1./-h 0 .lf-3 0. 70 3 /2.bb { 4. 4-/o (. 80 0.28 0.98 2a 2 {6.27 {.CCl/ 0.3/ I. 2'1 /8. (0. (, 83 .0.33 1.62 la **** 0.58 2.'20 1 -* : The reference point is selected as the initial free-end position of the geotextile specimen. ** r = 1 -lo Clo =The initial length between the two magnets) *** D = **** : Measured by dial gage

PAGE 130

119 LARGE BQX PUlLOUT TEST DATA SHEET Test No. : ----=2 __ Date : r-24--8f:J lb Temperature 68" _..:::......::.___ F Applied Force I 00 0 Total Movement : -2.5/ in Humidity : 40.0 (.%) Magnet Distance* Length Movement** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.> (in.) 7 o.ob 2,'75" 0, 0 ( 0.. 07 6 3. 0 ,. 6.-11 3. f{) 0.07 o. I 1./5 3.20 o:2.lf 0.38 4 Cf,3/ 3 .5L/. 0. 5"{ o. 8 <=t 3 12 .85" /.83 0.3 { /.20 Za /Jf. 68 1.83 0.33 /,53 2 16.5"/ /. 88 0.38 I, Cf I la {8.3? **** 0.60 2.5/ 1 -* : The reference point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 1o Clo = The in it 1 a 1 1 ength between the two magnets) *** : D = **** : Measured by dial gage

PAGE 131

120 LARGE BQX PULLOUT TEST DATA SHEET Test No. : 2 Date : I 24-8b Applied Force l05..0 1b Temperature 68 F Total Movement : 2. 9/ in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.> (in.) (in. > 7 0,/0 2.15 o. o I 0. I( 6 3,05 3./0 0.07 0.18 5 6./S 3.28 0.32 0.50 4 1.1/-3 3.62 0.5
PAGE 132

121 LARGE BOX PULLOUT TEST QATA Test No. 2 Date : I 24-86 Applied Force <]_50 lb Temperature 68 F Total Moverrent : 3,8/ in. Humidity : 40.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.> (in.) (in.) 7 0,47 2.9+ o.o I o. '1-8 6 3.1+( 3.17 0. 14-O.b2. 5 6.58 (O.Ob 3. 4-8 0.52 I. I 44 /3.83 3, 77 0.74 I. 88 3 I. 93 O.Lf./ 2.29 I /5. 7?:,' I 2a I I. Gf I O.J./.1 2.70 : 2 IJ. b 7 /.85 0,56 3.20 la (C(.SZ **** I . o.ss 3 81 1 -* : The reference pQint is selected as the initial free-end ; position of the geotextile specimen. ** r = 1 Clo = The in it 1 a 1 1 ength between the two magnets) *** D = **** Measured by dial gage

PAGE 133

122 LARGE BQX PULLOUT TEST DATA SHEET Test No. 2 Date : I 24-86 Applied Force 850 lb Temperature 68 F Total Movement : .lf. Gra in. Humidity : 40.0 (%) r.tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference .Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in. ) Cin.> (in.> 7 {).
PAGE 134

123 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 37Bb Ap p 1 i ed Force 0 lb Temperature 72 F Total Moverrent : 0 in. Humidity : 4-5.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 5 o. 00 J.5 I 0. 00 0.00 4a /.5/ [.50 o.oo 0.00 4 3. o I /.53 0. 00 o. 00 3a L/.51.//.5/ o. Do o. 00 3 6.0S 1.52 0.00 0. 00 2a 7.57 1 . 0b I.J/ o. 00 0.00 2 J.lf5 o. 00 0. 00 la (0.5/ **** --o. 00 1 : The reference point is selected as the initial free-end position of the geoteXtile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = **** Measured by dial gage

PAGE 135

124 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 37Bb . App 1 ied Force so lb Temperature 72 F . Total : 0 in. Humidity : IJ::.5.0 (%) Magnet No. 5 4a 4 3a 3 2a 2 la 1 ** *** **** Distance* Length Movement** Cumulative*** From Between Between Movement, Reference Adjacent Magnets, D Point, d Magriet, 1 r (in.) (in.) (in.) (in.) 0.00 /.50 0. 00 o. 00 /.50 /.Sf o.oo o.oo 3.0 I J.52. o. 00 o. 00 L/-.53 6. 01/-. I ,5J 0. 00 0. 00 /,b I 0. 00 0. 00 7.55 r.oJ/., o. 00 0.00 t.l/.7 0.00 0.00 /0.5/ **** -0.00 -The reference point is selected as the initial free-end position of the geotextile specimen. r = 1 lo Clo = The initial length between the two magnets) D = l:r Measured by dial gage

PAGE 136

125 LABGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7Bb Applied Force roo lb Temperature 72 F Total Movement : o. o I in. Humidity : 4-5.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between .Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in. ) 5 o.oo I /.SO (). 0 0 0. 00 4a !.50 /. 5" I 0.00 o.oo 4 3.01 l/-.53 .1.52. o.oo o.oo 3a /,52 0.00 0.00 3 .. 6.05" /.53 o.oo o.oo 2a J.Lf.7 0,00. 0.00 2 Cf.05" /. L/.7 o. 00 0. 00 la /O.fJ2 **** -o. o I 0. 0 I 1 : The reference point is selected as the initigl free-end position of the geotextile specimen. ** r = 1 -lo
PAGE 137

126 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7Bb Applied Force ISO lb Temperature 72 F Total lv'ioventent : 0.03 in. Humidity : Y:_s.o (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d _ Magnet, 1 r (in.) (in.) (in.) (in.) 5 0.00 ).5/ o. 00 0. 00 4a I ,5/ I .So 0. 00 0. oo 4 3. o I /.52 o. 0 0 0.00 3a L/..53 6.01/J. 5/ 0,00 o.oo 3 /.5,3 0. 00 0. 00 2a 7.57 Cj.os /. J./.8 0,00 0. 00 2 J. 11-8 0,0 0 0.00 la /0.53 **** -o. 03 0. 0.3 1 :The reference point is selected as the initial free-end position of the geotextile specimen. ** r = 1 lo
PAGE 138

127 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7-Bh Applied Force 200 lb Temperature 72 F Total Movement : (), 05 in. Humidity : 4-5.0 (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 5 o.oo /,50 o. 00 o.oo 4a t. s-o I .5/ o.oo 0. 00 4 3.0 J }.52 o.oo o.oo 3a 4-.53 {.51 0.00 0, oo 3 G. OJ.l. /.52 0,00. 2a 7.5"b I.Lf-r oo 0,00 2 Cf.OS /.ll-8 o. 00 o. 00 la /0.53 **** 0. 05 0.05. 1 : The reference point is selected as the initial frcG-end position of the geotextile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = ;rr **** Measured by dial gage

PAGE 139

128 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7-Bh Applied Force 250 lb Temperature 72 F Iota 1 Moveme'nt : o. /0 in. Humidity : Y:,5.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 5 0.00 1. 5 I 0, 00 0. 00 4a /.5/ J.50 o.o 0 o.oo 4 3.0 I 4-.5J./.. 1.53 0.00 0.00 3a /.5/ o.oo 0. oo 3 6.05 7.58 I-53 o.oo 0. 00 2a '. 5 I o. 02 0.02 2 'f .09 1.4-7 0. 00 0.02 la IO.S6 **** -D. 08 0. I 0 1 -. : The reference point is selected as the initial frcG-end posit.ion of the geotextile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D=rr **** Measured by dial gage

PAGE 140

129 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7-8'=> Applied Force 300 lb Temperature 72 F Total Movement : o. lb in. Humidity : Y:.s.o (%) tagnet Distance* length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent. Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.). 5 o. 00 t. 5 I 0, 00 -o oo 4a (.5/ I. 4-
PAGE 141

130 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 37Bf, Applied Force 350 lb Temperature 72 _...:....:;=--_F Total MovenEnt : Q,2/ in. Humidity : 4-5.0 (%) Magnet No. 5 4a 4 3a 3 2a 2 la 1 ** *** **** Distance* Length Movement** Cumulative*** From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) o. 00 /,5"0 o.ov oloo /.50 /.5 ( 0 ,DO O,Do :,,3,0 ( L/..51./-(,53 f), 00 o(vo 1.53 0.00. 0,00 6.07 I ,51/.. 0.02 0(02 7,6 I 1.52 0.03 oos Cf, r3 (,53 O.Ot+ ol oq 10.6./.. **** -o. f2 0,2/ -The reference point is selected as the initiQl free-end position of the geotextile specimen. r = 1 -lo Clo = The in it 1 a 1 length between the two magnets) D = Measured by dial gage

PAGE 142

131 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7Bb Applied Force LJ.oo lb Temperature 72 F Total Movement i 0.28 in. Humidity : Y:_s.o (%) f.1agnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.> (in.> 5 0.00 /,50 O,DO 0 00 4a 1,5"0 o,oo D,DV 4 3.02 l/..55 /.53 0,00 o.oo 3a 6.06 /,5' 0,00 0,00 3 /.Sb 0. D 1/w 0. 0/2a 7.62 '/ Jtl-/.52 0.03 0.07 2 (0. bb /,52 0. 0'/o. I I la **** 0.17 0.28 1 : The reference point is selected as the initial freeend position of the geotextile specimen. ** r = 1 -lo
PAGE 143

132 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 37Bf> Applied Force : L/.50 lb Temperature 72 F Total rv;overrtnt : 0.3b in. Hun1idity : '1.5.0 (%) Magnet Distance* Length Movement** Cumulative*** No. F-rom Between Between Movement, Reference Adjacent Magnets, .. D Point, d Magnet, 1 r (in.) (in.) (in.) (in.). 5 o.oo /,50 o o 0 o.oo 4a (.50 I J.5t D. oo 0.00 4 (.55 o. 0 I 0.02 3a 1/-.Sio /.52. o. 02 D. o 1./3 6.08 /.55 O.OUo. 08 2a 7.63 /,5L{. o.o F 0./3 2 /,52 o.os 0.18 la fO.b'f **** 0. t8 0.3b 1 -. : The reference point is selected as the initial frce-en' d position of the geotextile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** o = rr **** Measured by dial gige

PAGE 144

133 LARGE BOX PULLOUT TEST DATA SHEET Test No. 0 3 Date : 3-7-8b. 0 Applied Force soo lb Temperature : 72 F Total tl.ovement : o, Lf-'-? in. Humidity : ':1:5.0 (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 5 0, D L/-{,50 o.oo 0,0 t(. 4a J tfif. (,51 0.00 0, 0 1./. 4 3.05 f,SJ./. o. o 1 o,os3a }.5"3 o.o3 0(08 3 6.12 !.SCI 0,12 2a 7.7/ 9, 2L/-o,o.b o. (8 2 tO. 79 /,ss (),0 1 0,27 la 0, I 7 **** O,L/4 1 : The reference point is selected as the initial free-end position of the geotextile specimen. ** r = 1 lo <1o = The initial length between the two magnets) *** D=rr **** : Measured by dial gage

PAGE 145

134 LARGE BOX PULLOUT TEST DATA SHEET Test No. : 3 Date : 3-7-Bb Applied Force S50 lb Temperature 72 F Total Movement : o.s3 in. Humidity : Lf5.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent D Point, d Magnet, 1 r (in.> (in.) (in.) (in.) 5 (}( OL/-ooL/. /,SO lJ. 00 4a /, [)L/o. 00 o. otf 4 3.05 3a f./.,58 /,53 o. o I O,OS t.sJt. 0.03 0.08 3 6.12 (.58 0. Db 0. 1/. 2a 7. 70 f,Sb o. 07 0,2/ 2 1.5'1 0. I i. 0.33 la {0,83. **** -o. 20 0.53 1 -. : The reference point is selected as the initial frcG-end position of the geotextile specimen. ** r = 1 la Clo = The initial length between the two magnets) *** D = ;rr **** Measured by dial gage

PAGE 146

135 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7-Bf> Applied Force 600 lb Temperature 72a F . Total Movement : ()_. b L/. in Humidity : Lfs.o (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d 1 r (in.) (in.) (in.) (in. ) 5 o. 0 9 /,50 o. 00 o,o'f 4a /. 5'/ I .51 0. 00 0,0 't 4 3.10 J./.. 64-/,54 0. 02 0. I I 3a t .sb o. ot./:. Otl5 3 6.20 7,7? O. OJ 0,22 2a cr. 3J./.. 1.5S o7 D.2
PAGE 147

BOX IEST SHEEI Test No. Date : 3-7Bh Applied Force 6s-o lb Temperature 72. F Total Movenent : 0.71 in. Humidity : !f5.0 (%) t-1agnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (1n.) (in.) 5 o. II I. 5" I 0,0 0 I I 4a t.b2 {,50 o,oo 0, I I 4 3.12 4-.0h /.f>lf 0.02 0.13 3a b.22 I.S"b o. ()5 0.18 3 7.81/I. 62 o. o'f 0.27 2a 1(. tfl /.57 0.08 0.35 2 O.f(;, 1/.03 /,62 0.5'1 la **** 0.2b 1 -. : The reference point is selected as the initial frcs-end position of the geotextile specimen. 136 ** : r = 1 1. Cl. = The initial length between the two magnets) *** : D = rr **** : Measured by dial gage

PAGE 148

137 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 37Bh Applied Force : 700 lb Temperature 72 F Total Movement : o. 1 I in. Humidity : J+s.o (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) 5 D. I L/{.5/ oo 0. f Ll4a /.65 /.50 0. 0.0 0, I t.l4 3.1S 1.55 0. 03 0117 3a Lf. 70 /,Sb O.Ob 0,23 3 6.2b 0. f 0 0,33 2a 7.88 /,00 0.{.3 Lf.b 2 r. I. bl/-0.17 0,63 la tl.t2 **** 0.28 0. 91 1 : The reference point is selected as the initigl fras-end position of the geotextile specimen. * r = 1 -lo Clo = The initial length between the two magnets) *** D=rr **** Measured by dial gage

PAGE 149

. 138 LARGE BOX PULLOUT TEST PATA SHEET Test No. 3 Date : 3-7-Bf> Applied Force 750 lb Temperature 72 F Total Move"ent : Is .I 3 in. Humidity : 4-5.0 (%) f'.1agnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 . r (in.> C in.> < .in.) c in. ) 5 0.2/ 1.50 ;o.oo o,2 I 4a ./. 7 I 3.21 /,50 o. oo q,2 J 4 /.57 0.05 0.2b 3a Lf., 18 /.57 o.oh 0 .32 3 6.35 7-98 / .b2 0. t D 0. '-1-2 2a 9.62 /.bL/-' 0./5 0.57 2 /,68 0.2J 0.78 la {/.3 0 **** 0.35 /.13 1 ' : The reference point is selected as the initial frss-end position of the geotextile specimen. ** : r = 1 -lo
PAGE 150

139 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7-Bf> t Applied Force 775 lb Temperature 72 F Total Moverrent : I .I+ z in. Humidity : Y:_s.o (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent D Point, d Magnet, 1 r (in.> (in.) (in.) 5 {.50 0.34o. 00 4a J .84-(,5/ o. 00 0 .344 .. 3.35 1.1-.C/2 (,57 0, 05" 3a f, b I 0. 10 O.l-1-9 3 6.53 8./9 l.bb o. r4 0,63 2a Cf.8? (.70 0.20 0,83 2 f, 74 0 .25. 1.08 la ( /,b3 **** 0.3? /,J./.7 1 : The reference point is selected as the initial frse-end position of the geotextile specimen. ** r = 1 lo Clo = The initial length between the two magnets) *** D = rr **** Measured by dial gage

PAGE 151

140 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7-Bh Applied Force 750 lb Temperature 72 F Total Movement : /.86 in. Humidity : (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, 0 Point, d Magnet, 1 r (in.) (in.) (in.> (in.) 5 0.67 I, If 1 O. 00 o. 67 4a 2, t fo /j5 J 0 00 o.67 . 4 3.fo 7 /.57 o.os 0.12 3a 5. 2L/-6.Bt./. /. hO (), t 0 o. 82 3 /.55 0.13 0.'/S 2a f 1 0.2/ 1.16 2 '(,90 {/. b3 /.13 o.zt:, /.42 la **** 0. L/.1./-/.8(, 1 : The reference point is selected as the initial frse-end position of the geotextile specimen. ** : r = 1 1. Cl. = The in it 1 a 1 length between the two magnets) *** : D = rr **** : Measured by dial gage

PAGE 152

141 LARGE BOX PULLOUT TEST DAIA SHEET Test No. 3 Date : 3-.78b Applied Force : 675 lb Temperature 72 F Total : 2.22 in. Humidity : IJ:.s.o (%) t-1agnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.> (in.) 5 /. o I {.50 o.oo f, o I 4a /,5/ Lt.02 [.5/ 0.00 1.01 4 5.5"8 {.56 o.o4 /.I 5" 3a 7.t9 /. h t 0./0 1,25 3 8.90 /.11 o. t8 [. i/.3 2a (O.bZ /.72 0.23 I. "b 2 I 2. 2l/. /,62 O.IS I ,8 I la **** 0.1.1-1 2,22 1 : The reference point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo (1 .. = The initial length between the two magnets) ***:D=rr **** Measured by dial gage

PAGE 153

142 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7Bh Applied Force 500 lb Temperature 72g F Total Movement : 2.52 in. Humidity : 4-5.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Po.int, d Magnet, 1 r (in.) (in.) (in.) (in.> ,. 5 {. L/-3 /. 4-9 o,oo f. L.f-3 4a 2.92 /.5 'I (). 00 I. 4-3 4 lf..LI-3 /.Sb 9-OJ{.. t.J.J.7 3a 5. '1.'1 7.6/ {.b2 o. I I /.58 3 9,3/ (. 70 O.l7 /. 75 2a /,}0 o.21 t.'tfo 2 //.0/ /.fa 7 0.20 2. i la (2. .68 **** 0, 3f:J 2.52 1 : The reference point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 lv
PAGE 154

143 LARGE BOX PULLOUT TEST DATA SHEET Test No. 3 Date : 3-7-Bb App 1 ied Force Y-50 lb Temperature 72 F . Total Moverrent : in. Humidity : Y:_s.o (%) Magnet Di'stance* Length Movement** Cumulative*** No. From .Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.> (in.> (in.) 5 J. 80 /. tJ 9 0,00 {.80 4a : L/-,8/ (,52. 0.00 I ,80 4 ;-; /.5'5 0,03 /, 83 3a 6.3b 7/17 f,{;, I 0.10 /. Cf 3 3 f, 11 0.-18' 2 I I I 2a ?.68 t/.31 /.71 0.22 2.33 2 /.63 0. I b 2 la 13.02 **** O.itJ 2.crro 1 -* : The reference point is selected as the initial fres-end position of the geotext1le specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = rr **** Measured by dial gage

PAGE 155

144 LARGE BOX PULLOUT lEST DAI6 SHEEI Test No. 3 Date : 3-7Bh Ap p 1 i ed Force 4-00 lb Temperature 72 F Total Movement : 3.1./.0 in. Humidity : 'J:.5.0 (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) ,. 5 2.23 /.50 f), 00 2.23 4a 3.73 I ,5 J (), 00 2.23 4 s. 2L/-G.79 {.55 0.03 2.2b 3a 1.52 O . D I 2.27 3 8.31 (.68 0. 15' 2.42 2a 9.?9 /1.6 7 (. 68 0. t9 2. b f 2 t.IJ2 0.{5 2.7(D la /3.2..Cf **** -o. 61./.. 3. L/-0 -1 -* : The reference point is selected as the initial free-end position of the geotext1le specimen. ** : r = 1 lo Clo = The initial length between the two magnets) *** : D = Lr **** : Measured by dial gage

PAGE 156

145 LARGE BOX PULLOUT TEST DATA SHEET Test No. : Date : 3-7 Bh Applied Force 300 lb Temperature 72 F Total Moverrent : in. Humidity : Y:_s.o (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.) (in.> ,. 5 2.83 /. Ll-1 o. oo 2.83 4a L{. .3 2. ( .5'0 o. oa 2.83 4 5.82 7.30 /.Sl{o. 02 2.85 3a 8/17 l, 6 I 0./0 2. 95 3 /, 70 0. t 7 3.12 2a 10.67 /. {:, J/. .O.J!>. 3.27 2 /2.31 0.16 3. J./..3 la -**** O.l/-7 1 -* : The reference point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo Clo = The 1 nit 1 a 1 length between the two magnets) *** : D = Lr **** : Measured by dial gage

PAGE 157

146 LARGE BOX PULLOUT TEST DATA SHEET Test No. : Ji. Date : 3 14 8 b Applied Force 0 lb ---=---Temperature F Total Movement : ___ 0;.___ in. Humidity : __ #.._6_.;...:!>;__ (.%) Magnet Dis-tance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r Cin. > (in.) .(in.) (in.> .. 5 0 . 00 /.53 0. oo o.oo 4a J,53 /.63 0. 00 o. 00 4 3.06 /.5"2 0. 00 0,00 3a 1/-,58 J.s-L/-. 0.00 o. 00 3 6.12 I. L/.8 9.00 o.oo 2a 7.60 /.50 0. oo 0. 00 2 ?.to /.52. 0. 00 0. 00 la /0,62 **** -0.00 1 : The reference point is selected as the initial frcG-end position of the geotextile specimen. ** r = 1 10 Clo = The initial length between the two magnets) *** 0 = **** by dial gage

PAGE 158

. 147 LARGE BOX PULLOUT TEST DATA SHEET Test No. : 4 Date : 3-14--Bb Applied Force lb Temperature 7l 0 F Iota 1 Movement : 0 in. Humidity : Jt6.!) (%) t-1agnet D1stance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.) (in.) (in.> 5 0.00 [.53 .(!;00 o.oo. 4a '.53 3,0b {.53 0.00 o. 00. 4 1.52. o. oo o. oo 3a t/-.58 6.12 /.5'-1o. 00 o. 00 3 7.bo /. L/-8 0.00 0.00 22 0 /.so 0.00 o.oo 2 /.52 o. 00 0. 00 la 10.62 **** -0.00 1 -* : The reference point is selected as the initial free-end position of the geotextile specimen. ** r = 1 -lo Clo =The initial length between the two magnets) *** D = **** Measur.ed by dial gage

PAGE 159

148 LABGE PULLOUI TEST DAI6 Test No. 4 Date : 3-JJ./.-Bb Applied Force 100 lb Temperature 71 F Total Movement : o.ob in. Humidity : tl-6.5" (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.> (in.) 5 o. 00 /.53 0, 00 (), oo 4a I -7 1.53 0. () 0 o. 00 4 3.ob 1.53 f!J,OO 0. DO 3a 4-.59 G.12 (.53 0. 00 o.oo 3 7.6o /. tl-8 o.oo . 0.00 2c 'j. I I /. s1 0.00 o.oo 2 /.52. o. oo 0,00 la {0. 63 **** 0. DCJ O,Ob 1 -* : The referenc point is selected as the initial free-end position of the geotextile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = L"r **** : Measured by dial gage

PAGE 160

149 LARGE BOX PULLOUT TEST DATA SHEET Test No. 4 Date : Applied Force {50 lb Temperature ZL o F Total r..;ovement : 0.11./in. Humidity : /.1-6.5" (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r ; (in.) (in.) (in.) (in.) 5 0. oo /,53 o.oo o.oo 4a /!53 ; J.S3 o. 00 0. 00 4 3.0b (.53 0, 00 o. () 0 3a 1./-,s-q 6 ,12. (.53 0.00 o. 00 3 /.48 o. 00 o. 00 2c 7.bo 9. ( 0 /.50 o. 00 o. 00 2 ( 0. /.SS o. 03 0.03 la. **** 0. I I 0. 141 -* :The referencE:: point is selected as the initial free-end position of the geotextile specimen. ** r = 1 lo
PAGE 161

150 LARGE BOX PULLOUT TEST DATA SHEET Test No. J-1. Date : 3-IJ.I.-Bb Applied Force 2DO lb Temperature 7l 0 F Total l-1ovement : 0.2[ in. Humidity : tl-6.s-(%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 5 0, oo /.53 0. 00 (),00 4a (. !)l/0. 00 0. oo 4 3,07 (.52 0.00 0.00 3a (.53 0. ()0 0. f)O 3 (o.l 2 1.1./-8 0. 00 0.00 2a 7.b0 {.5D 0.01 0.0( 2 ? (0 o.o6 {.fifo 0. 05' la (O.bb **** 0,15" o. 21 1 : The reference point is selected as the initial frceend position of the geotextile specimen. ** : r = 1 lo Clo = The initial length between the two magnets) *** : D =I r **** : Measured by dial gage

PAGE 162

151 LARGE BOX PULLOUT TEST DATA SHEET Test No. 4 Date : 3-lt+_:Bb Applied Force 250 lb Temperature 7l 0 F Total flljovement : o. 2:.Z in. Humidity : (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, 0 Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 5 0; 00 (.52 0. 00 (),{)0 4a J,5Z /.5"4 o. oo 0.00 4 3.0b (.52 0. 0.0 o. 00 3a 1./-.58 6. ( 2. /,5/.f 0.00 -o. oo 3 (.50 0. D/ 0,0/ 2a 7. 62 Cj.r3 /.5/ 0. 0 { o.oz 2 /.60 o.o8 0.(0 la ( (). 73 **** 0,11 Q.27 1 : The reference point is selected as the initial frce end position of the geotextile ** : r = 1 10 Clo = The initial length between the two magnets) *** : D = L'r **** : Measured by dial gage

PAGE 163

152 LARGE BOX PULLOUT TEST DATA SHEET Test No. 4 Date : 3 ll.J.-Bb Applied Force 300 lb Temperature Zl o F Total llljovement : 0.31./. in. Humidity : tl-6. (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.) (in.) (in.) 5 (), 0 0 /.52 o. 00 o. 00 4a 1.52 L53 0.00 0. 00 4 3,05 L/-. f;Cf /.5tf o.oo 0. 00 3a 6.1'3' (.Sf o. 00 o.oo 3 7.63 {.SO o. o I o. o I 2a . (.52 .o. 02 0.03 2 ?./5 I. 6o o. 08 0. I I la I o. 75" ***'ir 0. 2.3 0.3 L/1 -* : The referencE: point is selected as the initial free-end position of the geotextile specimen. ** r = 1 -lo ( lo = The in it i a 1 1 ength between the two magnets) *** D = **** Measured by dial gage

PAGE 164

153 LARGE BQX PULLOUT TEST DATA SHEET Test No. 4 Date : 3-IJ.?-Bb Applied Force 350 lb Temperature 7l 0 F Total : o. 4./ in. Humidity : Jfb.5" (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, o Point, d Magnet, 1 r (in.) (in.) (in.) (in.> 5 o.oo I .511-o.oo 0. oo 4a ( .5t./3.07 (.53 0 oo o.oo 4 1./-. 6 0 {.53 D. 00 0.00 3a (.55 o.o I 0.0( 3 6. 15 ?. 67 1.52 0.03 O.Olf 2c. 9. tCf 1.52. 0.02, 0.06 2 t.b2._ 0. !0 o. 16 la {0.81 ***1: 0.25 0 .. Jf I 1 : The point is selected as the initial free-end position of the geotextile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = ,Lr **** Measured by dial gage

PAGE 165

154 LARGE BOX PULLOUT TEST DATA SHEET Test No. 4 Date : 3-llt-Bb Applied Force LfOO lb Temperature 7l 0 F Total Movement : 0 . 52 in. Humidity : 1./-6.5" {%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) {in.) (in.) {in.) 5 0, 0 l . /.53 0.00 o. o I 4a ( .SJ(. 0 .. 0( 0, Ol 4 3,08 { .51/-if. 62 0. 0 ( o. 03 3a b,tb (.51/. o.o ( O.Of 3 76Cf 0. {) 1-1-0.08 2a Cf, zs:-/.S6 6. Ill2 t,6t.J. 0. !Z la (D.8'f **** 0.2b. 0.52 1 -* : The refenmce point is selected as the initial free-end position of the geotextile specimen. ** r = 1 lo (1\) = The initial length between the two magnets) *** D = rr **** Measured by dial gage

PAGE 166

155 LARGE BOX PULLOUT TEST DATA SHEET Test No. J..l. Date : 3Ill-Bb Applied Force 4 lb Temperature 7l D F Total Movement : O.fi'/ in. Humidity : t/-6.5"" {%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r {in.) (in.) {in.) {in.) 5 o. o I {.53 0;0 0 tJ,Of 4a (, s-1../. 3.o9 J.5S o. o I o. 02. 4 4-.0i.J.. J.$ o.oz 0. OJ.f3a G. t Cf f.SS 0.02 0.06 3 7, 7I.J. /,55" 2a o.ob 0. 12 Cf.l2 /.58 0.08 0.20 2 ./' bfo 0. I J.t 0.34la **** o.2s 1 : The reference point is selected as the initial frcs-end position of the geotextile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = **** Measured by dial gage

PAGE 167

156 LARGE BQX PULLOUT TEST DATA SHEET Test No. : J.l. Date : 3-14-Bb Applied Force 500 lb Temperature Zl o F Total Movement : 0.70 in. Humidity : J.l.6.s-(%) Magnet Distance* Length Movement** .Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.> 5 0 *0:3 /.53 o.oo 0.03 4a /.Sb /.55 0. o I 0.04 4 3 I I 1.54 0. 0 { 0.0!> 3a l/..65 {.5"8 0, OS' o. (0 3 6.23 /.SI, o : Ob 2a 7.79 1. 6o 0. I o 0.26 2 'f, 3Cf . 1-bb 0. tt./o, 1/.() la //.05 **** 0.30 0.70 1 -* : The reference point is selected as the initial free-end position of the geotextile specimen. ** r = 1 -lo
PAGE 168

157 LARGE BQX PULLOUT TESI DATA SHEET Test No. J.l. Date : 3-tll--Bb Applied Force SoD lb Temperature Zl o F Total Movement : 0.85 in. Humidity : 1./-b.!) (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference 'Adjacent Magnets, o Point, d Magnet, 1 r (in ) (in.) (in.> (in.) 5 0. OJ./. 1.51./o.oo o, oif 4a /.58 I j 511-0,0' O. Of) 4 3. ( 2 J!,b1 [.57 0.02 0,07 3a b.'Zb 1.57 0;05. 0./2 3 7.81 {.55 2a 0 .Ob 0. (8 /. 62 0. t( 0 2 { {, 13 /, 70 0.18 0.4-7 la ***'#r 0. 58 0. 85" 1 -* : The reference; point is selected as the initial frcs-end position of the geotextile specimen. ** r = 1 -lo (lo= The initial length between the two magnets) *** D = **** : Measured by dial gage

PAGE 169

158 LARGE BOX PULLOUT TESTDATA SHEET Test No. J./. Date : 3-IJ.I.-Bb Applied Force 600 lb Temperature Zl o F Total Movement : o. 5 o. o7 /.53 0. 00 o. 07 4a I, 6 0 3. { 7 /.57 o. 0 2 o. () 4 1.55 0.0.3 o. 12. 3a 1/-,7 2 6.3/ o.oh o./8 3 t.bo 0.01 0. 27 2a 7 J Cj, Sl-//. 63 0. 12. 0.3? 2 i /,30 /.76 0.2.3 o.h2 la ***'!r -0.37 o. 1 : The referencE; point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 10
PAGE 170

159 LARGE BQX PULLOUT TEST DATA SHEET Test No. : 4 Date : 3-14-Bb Applied Force h50 lb Temperature Zl o F Total luiovement : /. 23 in. Humidity : L/-6.!) (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.> (in.) 5 o. IS sz o. 00 o. rs 4a /. 7 /.58 o.ot/0 t9 4 3;2S' . D. OJ./. 0.23 3a L/..8/ /. 6 I o.oh 0.2{ 3 6. /. b I o. 12 o. 4-( 2a 8 .olf. '!.73 0. '" o. 6o 2 /.78 o. 2.6 0.86 la I (.51 **** 0.37 /. 23 1 : The reference point is selected as the initial free-end position of the geotextile specimen. ** r = 1 lo Clo = The initial length between the two magnets) *** D = rr **** Measured by dial gage

PAGE 171

160 LARGE PULLOUT TEST DAI8 Test No. 4 Date : 3-lt+-Bb Applied Force 700 lb Temperature Zl o F Total : /. 61./in. Humidity : /.1-6.!) (%) tagnet Distance* length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 5 (),35 /.540, 00 0.35 4a l. /.58 0.05 OJ(-0 4 3.lf.7 1.5? o.ob 0.1/-b 3a 5.efo 1.65 0, I I 0.57 .3 6.7/ I. 6'f 0. IS 0.72 2a 8.35" J. 71./-O.ZJ./.. 2 fo,o{ /. 78 0.2/o 1.22 la ".87 I. 61/**** -0. 1+2.. 1 ---. : The reference: point is selected as the initial free-end position of the geotextile specimen. ** : r = 1 -lo (lo = The initial length between the two magnet?) *** : D = **** : Measured by dial gage

PAGE 172

161 LARGE BOX PULLOUT TEST DATA SHEET Test No. J.I. Date : 314-Bb Applied Force 625 lb Temperature Zl o F Tota l Movernent : 1.18 in. Humidity : 1.1-6.!> (.%) ; Magnet Distance* length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.> (in.) 5 o.s8 1.5Jf. 0.00 0.58 4a 2. I 2. 1.5'1 0.06 (). 6 1./. 4 3. 7/ I. bO 0. 07 0. 71 3a 5.3/ l.bb 0. IZ 0.83 3 6.<17 I. bb 0. I 7 1. 00 2a /.73 2 0.23 /.23 I. 0.27 1.50 la /2,15" ***"ic 0. Lf.B /. 'lB 1 -* : The reference point is selected as the initial free-end position of the geotextile specimen. ** r = l -lo
PAGE 173

162 LARGE BQX PULLOUT TEST DATA SHEET Test No. 4 Date : 3-ltJ-Bb Applied Force SYO lb Temperature Zl o F Total Movement : in. Humidity : J/.6.!) {%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in. ) (in.> Cin. > (in.> 5 f. 02 {.53 o. 00 I. 02 4a 2.55 1.00 o. 07 /, 4 L/-.15' L 6o :o.. 07 / I 6 3a 5,75 l.bJ./. 0. l 0 1.26 3 7.3/ I. 65' O.tC:, I. J.I.Z 2a (0,7b I. 72 0.22 I. 6J./.. 2 I. 7s-f). 23 I. 87 la /2. .s-1 0 5b **** 2.1/-3 1 : The reference; point is selected as the initial free-end position of the geotextile specimen. ** r '= 1 10
PAGE 174

163 LARGE BOX PULLOUT TEST DATA SHEET Test No. 4 Date : 3tlf Bb Applied Force J./.50 lb Temperature 7l 0 F Total Movement : z. '15 in. Humidity : J./.6.!) (%) Magnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.> (in.) (in.> (in.> 5 /.bb /.SL/o. o I (.61 4a 3,;2..0 J./..80 [. fo 0 0.01 1.14 4 /.60 o. 01 I. 8 I 3a 6 ,L/..0 1.64 o . 0 1.'11 3 l.b5o. t G 2.07 2a '} .6? I. 11 o.;u 2.28 2 II. J.I.O /3. o? /. 0. t 7 2.J.IS la **** 0,50 2. Cf5 1 : The referE.mce point is selected as the initial position of the geotextile specimen. ** r = 1 -lo Clo = The initial length between the two magnets) *** D = **** : Measured by dial gage

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164 'PULLOU! !EST DATA Test No. 4 Date : 3-ttl-Bb Applied Force 350 lb Temperature Zl o F Total llljoveri.ent : 3.bo in. Humidity : Jfb.t> (%) tagnet Distance* Length Movement** Cumulative*** No. From Between Between Movement, Reference Adjacent Magnets, D Point, d Magnet, 1 r (in.) (in.) (in.) (in.) 5 2.35 /.54 0. 00 2.35 4a [, 60 0.01 2.Lf2 4 5.4-/ 1.57 0. 0 L(. 2.4-6 3a 7.0b /. 63 o.o