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Geotextile Reinforcement on Flexible Pavement Roads ‫اﻟﻣرﻧﺔ اﻟﻣﺑﻠّطﺔ اﻟﻃﺮق ﻋﻠﻰ‬
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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013

1st International Conference for Geotechnical Engineering and Transportation ICGTE in24-15/4/2013

Effect of Geotextile Reinforcement on Flexible

Pavement Roads

Dr. Abdul Hadi Meteab AL Sa'adi

Asst. Professor, Babylon Tech. Inst.
Email: com.yahoo@Alkhiljan
Dr. Najah Mahdi Lateef Al-Maimuri
Asst. Professor, Babylon Tech. Inst.
Email: Najahml@yahoo.com.
Dler Abdullah Omar al-mamany
Asst. Lecturer, Kerkuk Tech. College
Email:Dlieromer@Yahoo.com

ABSTRACT
A field full scale flexible road is constructed and the effects of geotextile
reinforcement in paved road are tested by measuring the occurred rutting. The effect of
different numbers and positions of geotextile reinforcement using seven road sections are
evaluated and compared with unreinforced pavement section. It is found that a maximum
reduction of rut depth is 96% when using three reinforcement layers at three different
road layers interfaces, and a minimum reduction is 52% when using one reinforcement
layer at interface I ( between wearing and binder layers) under the effect of maximum
load cycles of 10000. The minimum Traffic Benefit Ratio (TBR= ratio between load
cycles on a reinforced section to that of unreinforced section for the same rut depth) is
found to be 4 when using one reinforcement layer in the interfaces I , and extremely large
values for other reinforcement cases. Once, the above values appear how the service life
of the paved road is increased by using geotextile reinforcement.
The cost-benefit analysis is also adopted in this research and found that by using one
reinforcement layer the road cost is increased by only 14% resulting in increment value
of TBR to 4 (this means that the road life is doubled 4 times if all other circumstances are
fixed). This is a minimum case benefit when comparing it with all other cases; it is found
that TBR values are exaggerated when different numbers and positions of geotextile
reinforcement layers are used.

Keywords: TBR, Geotextile, Road, Reinforcement Position, Rut Depth.

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

‫ﺗﺄﺛﯾر اﻟﺗﺳﻠﯾﺢ ﺑﺎﻟﻣﺷﺑﻛﺎت اﻟﺑوﻟﯾﻣرﯾﺔ ﻋﻠﻰ اﻟطرق اﻟﻣﺑﻠ ّطﺔ اﻟﻣرﻧﺔ‬

‫اﻟﺧﻼﺻﺔ‬
‫ﺗ م ﺑﻧ ﺎء طرﯾ ق ﻣ رن ﺣﻘﻠ ﻲ ﺑﺣﺟ م ﻛﺎﻣ ل وﺗ م ﻓﺣ ص اﺳ ﺗﺧدام اﻟﺗﺳ ﻠﯾﺢ ﺑﺎﻟﻣﺷ ﺑﻛﺎت اﻟﺑوﻟﯾﻣﯾرﯾ ﺔ‬
‫ ﺗ م ﺗﻘﯾ ﯾم ﺗ ﺄﺛﯾر ﻣﺧﺗﻠ ف‬.(ruts) ‫( ﻓ ﻲ اﻟط رق اﻟﻣﻌﺑ دة ﻋ ن طرﯾ ق ﻗﯾ ﺎس اﻻﺧﺎدﯾ د اﻟﺣﺎﺻ ﻠﺔ‬geotextile)
‫اﻋداد وﻣواﻗﻊ اﻟﺗﺳﻠﯾﺢ ﺑﺎﻟﻣﺷ ﺑﻛﺎت اﻟﺑوﻟﯾﻣﯾرﯾ ﺔ ﺑﺎﺳ ﺗﻌﻣﺎل ﺳ ﺑﻌﺔ ﻣﻘ ﺎطﻊ ﻟﻠطرﯾ ق وﻣﻘﺎرﻧﺗﮭ ﺎ ﻣ ﻊ ﻣﻘط ﻊ طرﯾ ق‬
‫ ﻋﻧ د اﺳ ﺗﺧدام ﺛﻼﺛ ﺔ طﺑﻘ ﺎت ﺗﺳ ﻠﯾﺢ ﺑﺛﻼﺛ ﺔ‬96% ‫ وﺟد ان اﻋﻠﻰ ﻧﺳﺑﺔ ﻟﻧﻘﺻﺎن ﻋﻣق اﻻﺧدود ھو‬.‫ﻏﯾر ﻣﺳﻠﺢ‬
‫ ﻋﻧ د اﺳ ﺗﺧدام طﺑﻘ ﺔ ﺗﺳ ﻠﯾﺢ واﺣ دة ﻓ ﻲ‬52% ‫ واﻗ ل ﻧﺳ ﺑﺔ ﻧﻘﺻ ﺎن ھ ﻲ‬,‫ﻣﻧﺎطق ﻓﺎﺻ ﻠﺔ ﺑ ﯾن طﺑﻘ ﺎت اﻟطرﯾ ق‬
. 10000 ‫ )ﺑﯾن اﻟطﺑﻘﺗﯾن اﻟﺳطﺣﯾﺔ واﻟراﺑطﺔ( ﺗﺣت ﺗﺄﺛﯾر اﻗﺻﻰ ﻋدد دورات ﻟﻠﺣﻣل ھ و‬I ‫اﻟﻣﻧطﻘﺔ اﻟﻔﺎﺻﻠﺔ‬
‫ = اﻟﻧﺳ ﺑﺔ ﺑ ﯾن ﻋ دد دورات اﻟﺛﻘ ل ﻟﻠﻣﻘ ﺎطﻊ اﻟﻣﺳ ﻠﺣﺔ اﻟ ﻰ ﺗﻠ ك‬TBR) ‫وﺟد ان اﻗل ﻧﺳﺑﺔ ﻟﻼﺳﺗﻔﺎدة اﻟﻣرورﯾﺔ‬
‫ وﺑﻘﯾﺔ اﻟﻘﯾم ﻋﺎﻟﯾﺔ‬, I ‫ ﻋﻧد اﺳﺗﻌﻣﺎل طﺑﻘﺔ ﺗﺳﻠﯾﺢ واﺣدة ﻓﻲ اﻟﻣوﻗﻊ‬4 ‫اﻟﻐﯾر ﻣﺳﻠﺣﺔ ﻟﻧﻔس ﻋﻣق اﻻﺧدود( ﻛﺎﻧت‬
‫ ان اﻟﻘ ﯾم اﻋ ﻼه ﺗظﮭ ر ﻛﯾﻔﯾ ﺔ زﯾ ﺎدة اﻟﻌﻣ ر اﻟﺧ دﻣﻲ ﻟﻠطرﯾ ق اﻟﻣﻌﺑ د ﻋﻧ د‬.‫ﺟ دا ﻓ ﻲ ﺣ ﺎﻻت اﻟﺗﺳ ﻠﯾﺢ اﻻﺧ رى‬
.‫اﺳﺗﺧدام ﻣﺷﺑﻛﺎت اﻟﺗﺳﻠﯾﺢ اﻟﺑوﻟﯾﻣﯾرﯾﺔ‬
‫ ﻓ ﺎن ﻛﻠﻔ ﺔ‬,‫ﻛذﻟك ﺗم اﻋﺗﻣﺎد ﺗﺣﻠﯾل اﻟﻛﻠﻔﺔ واﻟﻔواﺋد ﻓﻲ ھذا اﻟﺑﺣ ث ووﺟ د ان اﺳ ﺗﺧدام طﺑﻘ ﺔ ﺗﺳ ﻠﯾﺢ واﺣ دة‬
‫ )وھ ذا ﯾﻌﻧ ﻲ ان ﻋﻣ ر اﻟطرﯾ ق ﻗ د‬4 ‫( اﻟ ﻰ‬TBR) ‫ وھذا ﯾؤدي اﻟ ﻰ زﯾ ﺎدة ﻗﯾﻣ ﺔ‬14% ‫اﻟطرﯾق ﺗزداد ﺑﻧﺳﺑﺔ‬
‫ ان ھذه اﻟﻔﺎﺋدة ھﻲ اﻟﺣد اﻻدﻧﻰ ﻋﻧد ﻣﻘﺎرﻧﺗﮭﺎ ﻣﻊ‬.(‫ ﻣرات اذا ﻛﺎﻧت ﺟﻣﯾﻊ اﻟظروف اﻻﺧرى ﺛﺎﺑﺗﺔ‬4 ‫ﺗﺿﺎﻋف‬
‫( ﻋﻧ د اﺳ ﺗﺧدام أﻋ داد وﻣواﻗ ﻊ ﻣﺧﺗﻠﻔ ﺔ ﻟطﺑﻘ ﺎت‬TBR) ‫ﺑﻘﯾ ﺔ اﻟﺣ ﺎﻻت ﺣﯾ ث وﺟ د ان ھﻧﺎﻟ ك ﺗﻌ ﺎظم ﻓ ﻲ ﻗ ﯾم‬
.‫اﻟﺗﺳﻠﯾﺢ اﻟﺑوﻟﯾﻣﯾرﯾﺔ‬

INTRODUCTION

T he application of vehicular load to a flexible pavement results in dynamic stresses

within various pavement components [1]. As vehicular loads are repeatedly
applied, permanent strain is induced in all layers of flexible pavements and
accumulates as traffic passes grow, which leads to rutting of the pavement surface. The
rutting appears at the surface of flexible pavement can be caused by shear deformation
within bituminous mixtures and/or by plastic deformation in the underlying unbound
layers (foundation, subsoil ….etc.) [2].
Bertuliene et al. (2011) [3] indicated that Ruts otherwise called a wheel path, are one
of the most frequent defects of asphalt pavement which related to shear strains are
difficult to be calculated and modeled due to the following difficult obstructs; material
characteristics relation is too complex, dependent, and non-linear, permanent changes of
material properties under the effect of dynamic loads and temperature. Many others
(Perkins and Islamic (1997) [4], Al Saadi (1997) [5], Benjamine et al. (2009) [6],
Moayedi et al. (2007) [7], and Holtz et al. (1998) [8]) used geosynthetic reinforcement
into unpaved and paved flexible roads. They concluded that in most cases, reinforcement
improves the performance of transportation support due to improving the effective
bonding between asphaltic concrete and geosynthetic, prevention of local shearing of sub

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

base and subgrade, and also improving load distribution through the base coarse,
reduction or reorientation of shear stresses of the subgrade and tension membrane effect,
increase bearing capacity of the subgrade, stiffens the base layer by reducing normal
stresses. Giroud et al. (1984) [9] Stated geosynthetic restricts lateral movement of the
base course material and subgrade and can provide tensioned membrane support where
deep rutting occurs.
Benjamin et al. (2009) [6] and Christopher (2010) [10] investigated the improvement
of flexible roads when geosynthetic reinforcement placed at the interface between sub
base and subgrade layers. Whereas, many others (Zomberge and Gupta (2010) [1],
Christopher (2010) [10] and Perkins et al. (2009) [11]) studied the behavior of flexible
paved road under the effect of the reinforcement placed at the bottom of the base layer.
Other researchers (Moayedi et al.(2007) [7], IGS (2006) [12], Laurinavicius and Oginkas
(2006) [13] and Grawbowski and Pozarycki ( 2008) [14]) investigated the properties
changes of flexible pavement when the reinforcement is placed within asphaltic concrete
layer or between the interface of any two consecutive layers or between asphaltic and
granular aggregate layers.
Since Al saadi (1997) [5] there are a few serious laboratorial modeled studies and no
full scale in-ground field test is achieved in Iraq. To simulate a true effect of truck load
cycles and to investigate the flexible paved road response, a full scale field road
constructed by using several cases of geosynthetic reinforcement (seven cases in current
study) with available construction materials. The development in this study, one or more
reinforcement sheets are ubiquitously used and the resulting asphaltic pavement response
is observed.
Goals
In the middle and south Iraqi roads, a permanent deformation is the major problem
encountered in flexible pavement roads which may be attributed for one or more reasons
such; high summer temperature, truck heavy axle load; method of design, pavement
constructed materials, construction priorities, compaction, and testing technology. The
following main goals are undertaken in this research.
1- The effect of geotextile reinforcement on light paved roads is aimed to be
investigated.
2- Cost-benefit study is developed to evaluate the use of geotextile reinforcement in
flexible paved roads.

METHODOLOGY OF THE WORK

A temporary roadway is designed and constructed in the field to allow some rutting to
be occurred over a visible life of flexible road to save time and labor. Several steps are
followed in this research; they are:-
1- Field geotextile reinforcement with Iraqi construction materials are used to
construct the field model show in Figure (1).

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

2- Seven reinforcement cases is suggested for better understanding of flexible

pavement road behavior for the expected dynamic axle loads are positioned in
interfaces I,II&III as shown in Figure (2).

MODEL CONSTRUCTION AND TESTING

A full scale field flexible pavement road of 28m long and 4.6m wide is carefully
constructed and trafficked to compare the relative performance of each individual section
B, C, D, E, F, G, H, and I as shown in Figure (1) against the applied dynamic axle loads.
Each section of the pavement road is suggested to be reinforced with geosynthetic
Reinforcement. For instance, for zone-B of Figure (1), reinforcement layer is placed in
the interface between the wearing and binder layer namely (I). To facilitate reinforcement
methodology of each section of Figure (1), Table (1) shows the details of how each
section has been reinforced.
The road section of field model shown in Figure (1) is connected with 1m paved and
5m unpaved straight road sections to facilitate vehicle entrance and exit and to avoid the
unfavorable effects of impact, wheels torque due to turning, and vehicular acceleration
and/or deceleration. The end limps of straight road of Figure (1) is completed with two
unpaved circular roads of 22m outer diameters and provided with supper elevation to aid
in vehicular rotation without deceleration and/or acceleration.
The distance of each truck travel (load cycle) is about 90m.This offer cycle time about
13sec. (equivalent to 275 truck pass/hr) when average truck speed rate is 25km/hr.
104 truck cycles were done in two weeks during June, 2012. This trafficking time is
chosen for highest temperature rates in Iraq (average temperatures of 43C⁰) to investigate
the effect of worst case of road pavement rutting [15].
Preliminary preparation are undertaken for the field site such as cleaning, land
leveling and grading by using lightweight grader, unrolling and fitting of the geotextile
rolls according to the design section of the model of Figures (1&2) before any testing.
Textile rolls are spread and overlapped (400mm) manually (geosynthetic overlap in
between (300-450mm) when CBR of subgrade soil is ≥ 3% [12]).
The meshes of the geotextile rolls Figure (3c) are fixed to be in contact pavement layer
surfaces by anchored pins (for soil surfaces) or hilted screws ( for paved surfaces) at a
rate of 2/m2.
Tack coat at interface I and prime coat at interface II are spread according to Iraqi
specification [16]. After the geotextile mesh has been placed, tack and prime coats are
added to improve bonding of contacting surfaces. Back dump of base materials and
spread it to the design thickness and compact it. Asphaltic binder and wearing materials
are provided and spread using spreader machine. The required properties for the whole
model construction are compared with Iraqi specifications [16].

LOADS ANALYSIS
The analysis of loading is conducted by vehicle of tandem axles having a dual tires
rear axle and a single tire front axle. The truck is overloaded with 98kN rear axle and

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Pavement Roads

49kN front axle which lead to load of 24.5kN for each wheel. According to tire size, it is
found the pressure of each is 830kPa (120psi).

RUT MEASUREMENTS
Traverse measurements of uplift and down-lift ruts across road sections are taken
during trafficking for every 1000cycles by installing 100mm mechanical dial gauge of
0.1mm sensitivity. This gauge is provided by additional 76mm extension part to be
used for reading of rutting in control section.
To obtain higher accurate dial indicator readings in the period of the test, a rigid iron
beam Figure (3d of 4.6m) is provided with a uniform stable support for the dial indicator
and can be easily positioned and locked for each 100mm on the beam. Each side of the
beam has two legs which set at constant, limited, and previously leveled points at each
end of cross section. The dial readings for each section are 45, one in the road centerline
and 22 for right and left sides.

FULL SCALE ROAD CONSTRUCTION & STRATIFICATION

Very light traffic flexile roadway plan and section Figures (1&2) and photos Figures
(3a, b) is designed to facilitate testing process. The model cross-sectional profile is
consisted of the following layers:-
- 50mm of asphaltic wearing layer with nominal aggregate size of 12.5mm.
- 70mm of asphaltic binder layer with nominal aggregate size of 19mm.
- 180mm of gravel and sand mix base layer of nominal aggregate size of 37.5mm.
- Infinity depth of ordinary in-situ weak subgrade soil.
Some testing properties of the above layers materials are listed in Tables (2, 3).
The reinforcement used in this study is the geotextile of aperture size 34mm in vehicle
direction and 24mm across vehicle direction. Some properties of geotextile are listed in
Table (4).
The laboratory CBR test for the base layer is conducted according to ASTM (1987)
[17] using 24hr saturation time, it is found to be 25%, Whereas the field CBR of the
subgrade soil according to SOIL TEST (1967) [18] is found to be 3% , it is also found
that the moisture content, Liquid Limit, and Plasticity Index of 18%, 48%, and 22%
respectively. The filler (1.5% of total aggregate weight) is also used with Ordinary
Portland Cement.

RESULTS AND DISCUSSION ay layer cu =50

Figures (4-11) present the field rutting measurement of the reinforced and
unreinforced pavement road sections. The rutting values reflect the effect of geotextile
reinforcement with seven different positions by comparing with control pavement section
(section with no reinforcement or Nile). These figures are show the difference in rut area,
shape changes, and sections (deformation) behavior under the effect of load cycle
variation. The values of up-lift, down-lift and total ruts are summarized in Table (5) and

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Pavement Roads

represented graphically in Figures (12 and 13). Table (5) reveals how these ruts are
exaggerated under the effects of number load cycle repetitions (N). Figure (12) presents
the relation of rut depth versus different numbers and positions of geotextile
reinforcement. To illustrate this, consider for instance the load cycle 10000. The curve
shows a high reduction in rut depth in case of one or more reinforcement layer is used,

this from one hand. It is also found the position of reinforcement layer has also a major
effect on reduction of rutting values and increasing the economical road life.
Figures (12 & 13) indicate that when one reinforcement layer is positioned at interface
II, there are some improvements of road performance but less than that if it is positioned
in the interface
III. Rutting has been induced and accumulated the lateral strain permanently in the
base aggregates as traffic load cycles are proceeded.
In case of reinforcement position in the interface I, the effect of the reinforcement on
rutting reduction is too little comparing it with the positions of reinforcement in the
interfaces II and III. This is attributed to that the reinforcement of interface I provide
Lateral traverse resistance due to frictional and interlocking forces between geotextile
sheet and bottom of
Wearing layer. This position of reinforcement reduces the physical activity of the
geotextile sheet. Fortunately, this position increases membrane support of wheel loads
and the bearing capacity of failure zones within the considered pavement layers to
enhance the shear strength of the interface I [10].
Figures(12, and 13) Also indicate that in case of using two reinforcement layers (in
three different positions I+II, I+III, and II+III) or three reinforcement layers, the
interpretation to this is that the pavement behavior under the effect of simultaneous
employment of the three positions of geotextile reinforcement is too complex to be
understood. This is attributed that there is an accumulative improvement that occurred
ubiquitously due to the placement of the three reinforcement layer in the considered
interfaces.
By using Traffic Benefit Ratio TBR (TBR = NR/Nu Where NR = No. of load cycles on
a reinforced section, Nu = No. of load cycles on unreinforced section for the same rut
[19]) for rut depth= 45mm, as in Figure (12), it is found that TBR= 4, 6.3 for one layer in
the interfaces I, and II respectively, and extremely large values for other reinforcement
cases. Once, the above values reveals on how the service life of the paved road is
increased by using geotextile reinforcement.
By using, Table (6) and Figure (14), to analyze the cost-benefit of using geotextile
reinforcement in paved road, it is found that (for rut depth=45mm) by Using one
reinforcement layer leads to increase the road cost by only 14% but it is found that the
corresponding increment in TBR is 4. This is the minimum benefit in this case by
comparing it with all other cases including different numbers and positions of reinforced
layers. This means that an exaggerated TBR values is obtained for few increment of
reinforced road cost.

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Pavement Roads

CONCLUSIONS
The followings may be concluded in this research:-
1- Multi-geotextile reinforcements of paved road offer less rutting than single geotextile
reinforcements.
2- Triple reinforcement layers, namely (I+II+III) reduces the amount of rutting depth by
96%.
3- Interface III reinforcement is best case to reduce Rutting if a single reinforcement
layer is used. The cost increasing of 14% results in rutting reduction of 85%.
4- If two layers of reinforcement is used, II+III reinforcement interfaces is the best case
since it offers rutting of 93% whereas, the increasing in cost is 28% by comparing it
with the control section (Nile).
5- If three layers of reinforcement is used, I+ II+III reinforcement interfaces offers
rutting of 96% whereas, the increasing in cost is 42% by comparing it with the control
section (Nile).
6- For 45mm rut depth, a significant increase in TBR is occurred of 4, 6.3 for one layer
of interfaces reinforcement I and II respectively. This can be attributed that road
service life doubled 4 and 6.3 times in case I and II interfaces respectively when other
circumstances are fixed.

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[16].NCCL, MATERIALS SPECIFICATION AND CONSTRUCTION WORKS,
Baghdad, Iraq, (2001).
[17]. ASTM, ANNUAL BOOK OF ASTM STANDARD, USA. , 1987.
[18]. SOIL TEST, SOIL TEST Inc. General Catalog, USA. ,(1967).
[19]. Berg R.R., Christopher B.R. and Perkins, S.W., “Geosynthetic Reinforcement of
the Aggregate Base/Subbase Courses of Pavement Structures GMA White Paper
II, Geosynthetic Materials Association, Roseville, MN, P.176, (2000).

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

Table (1) Definition of the Model Sections Reinforcement.

Section Naming of reinf. Details & Description

position
A - Entrance and Exit Zone
B I Reinforcement in the interface between the
wearing and binder layers
C II Reinforcement in the interface between the binder
and the Base Coarse layers
D III Reinforcement in the interface between the Base
Coarse and Subgrade
E I+II Reinforcement of interfaces I and II are used
ubiquitously
F I+III Reinforcement in interfaces I and III is used
ubiquitously
G II+III Reinforcement in sections II and III is used
ubiquitously
H I+II+III Reinforcement in sections I, II, and III is used
ubiquitously
I without Control Section(Without Reinforcement)
Reinforcement
J - Entrance and Exit Zone

Table (2) Physical Properties of Asphalt Cement (Al-Nasyria Refinery).

Test ASTM Test Result Iraqi SORB

Definition Specification
Specific Gravity D-70 1.057 -
Ductility D-113 118cm >100
Kinematic D-2170 415Cts -
Viscosity
Penetration D-5 52 40-50 south of Iraq
50-60 middle of Iraq
60-70 North of Iraq
SORB one part of the National Center for Construction Laboratory (NCCL, 2001)

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

Table (3) Gradation of Aggregates Results.

Sieve Grading of Road Materials
Size
mm Wearing Layer Binder Layer Base Layer

Result, Specification Result, Specification Result, Specification

% Limits, % % Limits, % % Limits, %
37.5 100 100
25 100 100 81 75-95
19 85 80-100 - -
12.5 100 100 69 60-84 - -
9.5 88 80-100 59 49-74 56 40-75
4.75 60 46-76 40 32-58 43 30-60
2.36 41 28-58 31 23-45 31 21-47
.30 17 8-24 12 8-20 19 14-28
.075 9 4-12 5 3-8 8 5-15

Table (4) Properties of Geotextile Reinforcement*.

Property Unit Vehicle Direction Cross Vehicle
Direction
Unit Weight gm./m2 330 330
Aperture Size mm 34 24
Peak Tensile KN/m 17 25
Strength
Tensile Strength at KN/m 5 8
2% Strain
Yield Point Strain % 9 8
*According to Sinan Factory Properties, Izmir, Turkey

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

90m
25m 5m 1m 28m 1m 5m 25m

1m 3.5m 3,5m 3.5m 3.5m 3.5m 3.5m 3.5m 3.5m 1m 12m

7

A B C D E F G H I J
A

Figure (1) Plan View of Full Scale Flexible Road Model.

220cm

5cm I
Wearing Layer
7cm II

Binder Layer
18cm
III
Base Layer

Subgrade Layer 460cm

=∞
Figure (2) Cross Section A-A (as shown in Figure (10).

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

a) High Plasticity Subgrade b) Wearig Layer Layout

c) Geotextile Reinforcement Roll d) Rigid Iron Beam

Figure (3) Some Site photos.

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

Figure (4) Rut Depth for Interface I

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

Figure (5) Rut Depth for Interface II.

Figure (6) Rut Depth for Interface III.

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

Figure (7) Rut Depth for Interfaces I+II

I+II.

Figure (8) Rut Depth for Interfaces I+III.

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

Figure (9) Rut Depth for Interfaces II+III.

Figure (10) Rut for Interfaces I+II+III

I+II+III.

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
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Figure (11) Rut for Control Section.

Figure (12) Rut Depth for Different Load Cycles and Interfaces.

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Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
Pavement Roads

Figure (13) Rut Depth versus Numbers & Positions of Reinforcement

Lawyers for Load Cycles=10000.

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 Eng. & Tech. Journal, Vol.Part (A) , No. 20 , 2013 Effect of Geotextile Reinforcement on Flexible
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Figure (14) Cost Analysis of Reinforced and

Unreinforced Road Sections.

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