PRS-NEOWEB™
Earth Stabilization
Erosion Control, Slope
Protection & Earth Retention
PRS-EN-TD-ER-2001 Ver. 13.01
TECHNICAL
OVERVIEW
© 2013 Copyright and Proprietary of PRS. Certain products and/or applications described or
illustrated are protected under international patents. Final suitability of any information or material
for use and its manner of use is the sole responsibility of the authorized user.
Contents
PRS-NEOWEB CELLULAR CONFINEMENT SYSTEM ...................................................................................3
SLOPES ................................................................................................................................................... 3
EARTH RETENTION................................................................................................................................. 3
DURABILITY ............................................................................................................................................ 4
BENEFITS OF PRS-NEOWEB EARTH STABILIZATION............................................................................... 4
PRS-NEOWEB EARTH STABILIZATION SOLUTIONS ................................................................................ 5
SUSTAINABLE SOLUTION ....................................................................................................................... 5
PRS ......................................................................................................................................................... 5
CHOOSING THE PRS-NEOWEB CATEGORY............................................................................................. 6
Tables of PRS-Neoweb® Categories (A-D) ........................................................................................6
VEGETATED SLOPE PROTECTION (A) ........................................................................................................8
PRS-Neoweb Slope Cover Protection System ..................................................................................8
VEGETATED SLOPE PROTECTION (B) ........................................................................................................9
PRS-Neoweb Slope Cover Protection System ..................................................................................9
GRAVITY RETAINING WALL ....................................................................................................................10
PRS-Neoweb Gravity Retaining Wall of Horizontal Layers .............................................................10
REINFORCED RETAINING WALL ..............................................................................................................11
PRS-Neoweb Retaining Wall with Geogrid Reinforcement............................................................11
EARTH RETENTION & STABILIZED EROSION CONTROL ...............................................................................12
Combined PRS-Neoweb Gravity Retaining Wall & Back Slope Protection.....................................12
STEEP EARTH STABILIZATION .................................................................................................................13
PRS-Neoweb Fascia Wall ................................................................................................................13
SOIL-NAILING HIGH & STEEP EARTH STABILIZATION .............................................................................14
PRS-Neoweb Fascia Wall & Slope Stabilization & Soil-nailing........................................................14
REFERENCES ...........................................................................................................................................15
PRS-Neoweb for Earth Retention – Seismic Research (Leshchinsky, D., et al, University of
Delaware, USA)...............................................................................................................................15
PRS-Neoweb Railway Embankment Testing (Leshchinsky, B., Ling, H., et al, University of
Columbia, USA)...............................................................................................................................15
Additional References ....................................................................................................................15
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Rev. 13.01
PRS-NEOWEB CELLULAR CONFINEMENT SYSTEM
The PRS-Neoweb System is a soil confinement, stabilization and reinforcement solution developed,
manufactured and marketed by PRS, comprised of three-dimensional, perforated and textured
honeycombed geocells. PRS-Neoweb can be applied to a wide range of soil stabilization applications
subject to surface erosion and unstable slopes, including slope and channel protection, earth
retention and stabilization, and reservoirs and landfills.
SLOPES
PRS-Neoweb confinement along with anchoring techniques ensures the long-term stability of slopes
using vegetated topsoil, granular infill or concrete surfacing. The enhanced drainage, frictional forces
and cell-soil-plant interaction of PRS-Neoweb prevents downslope movement from hydrodynamic
and gravitational forces. PRS-Neoweb slope protection is provided by:
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Frictional resistance which
reduces sliding
Cell walls that mechanically
protect against run-off, rill
development and erosive
forces
Soil confinement, which
enhances soil particle
structure and soil integrity,
minimizing the impact of
raindrops
Cell perforations facilitating
plant and root interlock,
thereby stabilizing the soil
mass
The PRS-Neoweb system tolerates high sheet-flow conditions and prevents channeling by limiting
flow and increasing hydraulic shear stresses. PRS-Neoweb slope protection is also applicable to
Channel Protection. PRS-Neoweb confinement of vegetated soil, hard armor or poured concrete fill
optimizes erosion protection for natural or man-made channels and hydraulic structures, typically
incorporated into open-channel systems.
EARTH RETENTION
Retention structures are typically used where earth slopes are impractical due to sharp grade
changes, irregular topography, or lack of land within a project site. PRS-Neoweb retaining walls
provide steep vertical earth retention (up to 81°) that are structurally stable under self- weight and
externally imposed loads. Gravity and reinforced walls erected with stacked PRS-Neoweb system
layers maintain structural stability, even in compressible and unstable foundation subgrades.
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DURABILITY
PRS-Neoweb is comprised of
advanced polymeric alloys that
make the cellular confinement
system stiff, flexible and durable. In
particular the PRS-Neoweb patentpending alloys feature long term
dimensional stability, high long
term design strength (creep
resistance) and low reduction
factors. This translates to a longer
life-span for PRS-Neoweb earth
retention structures. In addition,
PRS-Neoweb is non-degradable and
is resistant to weathering, extreme
temperatures and water, which can
affect concrete, steel and timber
solutions.
BENEFITS OF PRS-NEOWEB EARTH STABILIZATION
Design & Construction
 Geocells – physically protect against run-off, rill and gully formation and erosive forces
 Frictional resistance – reduces soil sliding & migration
 Cell perforations – facilitate plant and root interlock to further stabilize soil mass and slope
Material
 Unique Neoloy® polymer technology - high resistance to UV, oxidation, water, extreme
temperatures
Erosion Control
 Soil confinement – enhance soil structure and minimizes impact of raindrops
 Drainage – promote infiltration and limit the impact of hydrostatic forces
Economic
 Cost effective –reduces the quantities of surface cover required (topsoil, gravel or concrete)
 Long lifespan – maximizes project lifecycle costs
 Low installation cost and Total Cost of Ownership
Environmental
 Sustainable - enables flow of water, nutrients and soil organisms
 Landscape – enhance plant growth, soil health and visual landscape
 Permeability of PRS-Neoweb wall perforations facilitates onsite drainage and stormwater
management.
Earth Retention
 Neoloy-based PRS-Neoweb offers very long-term stiffness and strength.
 PRS-Neoweb absorbs energy making it highly resistant to seismic activity.
 Construction without forms or curing is faster than poured concrete.
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PRS-NEOWEB EARTH STABILIZATION SOLUTIONS
SLOPE PROTECTION
EARTH STABILIZATION
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Transportation and Construction
– Cut slopes
– Road and rail embankments
– Abutment protection
Energy
– Storage facility berms
– Pipeline stabilization
Environmental
– Green roofs
– Mine and quarry restoration
Reservoirs
– Ponds, lagoons, dams
– Channel and shoreline structures
Landfill
– Waste containment facilities
– Waste rehabilitation sites
Transportation and construction
–
–
–
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Rehabilitation
–
–
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Energy and noise absorbers
Green walls
Channels and Coastlines
–
–
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Mine site and quarry restoration
Failed slopes
Environmental
–
–
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Multi-grade transportation arteries
Green road and rail embankments
Safety barriers
Storm water structures
Coastal cliff preservation
Site grading
–
–
Expanding fields and yards
Grading site to boundaries
SUSTAINABLE SOLUTION
PRS-Neoweb is the best-available sustainable solution for long-term soil protection and stabilization
in slopes, embankments and retaining walls. PRS-Neoweb improves site ecology by enhancing water
drainage and soil quality, and when integrated with revegetation schemes, improves the site
landscape, soil food web and visual aesthetics.
The PRS-Neoweb perforations promote infiltration and limit the impact of hydrostatic forces by
improving drainage. This plays a crucial role in soil protection by:
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Preventing run-off and soil erosion
Preserving the soil structure
Enabling flow of water, nutrients and soil organisms
Healthy soil encourages the growth of vital soil organisms and processes that improve nutrient
cycling, porosity and soil aggregation. The perforations are also critical in promoting revegetation by
providing an excellent growth environment for roots and plants. This further stabilizes the soil and
slope, while facilitating the restoration of the vegetation and landscape.
PRS
PRS is the world’s leading supplier of cost-effective earth stabilization solutions. Combining unique
proprietary technology with specialized engineering expertise, PRS delivers proven solutions for load
support, slope and channel protection, earth retention, and reservoir and landfill applications. With a
global network of regional offices and local distributors, PRS provides a full range of end-to-end
support services. Since its establishment in 1996, PRS has implemented hundreds of successful
projects in over 45 countries worldwide.
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Rev. 13.01
CHOOSING THE PRS-NEOWEB CATEGORY
The following table explains how to select the PRS-Neoweb that matches the actual needs of the
project, pre-calculated by typical stresses, loading, photochemical durability, elevated temperatures
and design-life and not just the cell dimension. Different cell sizes and heights are available
according to design objectives.
The PRS approach departs from the commonly accepted practice of using standard strength (HDPE)
geocells (of different sizes and heights) for all project types, and takes into account the project design
requirements, thereby avoiding over- or under-design.
Tables of PRS-Neoweb® Categories (A-D)
PRS-NEOWEB CATEGORIES – GENERAL
A
Suitable for low to
moderate slopes and
flow velocities
B
C
D
Suitable for moderate
to high slopes and flow
velocities
Suitable for very steep
slopes & very high
flow velocities
Suitable for the most
demanding slope and
channel solutions
PRS-NEOWEB VS. SLOPE TYPE CATEGORIES – DETAILED SUITABILITY
PRS-NEOWEB GEOCELL CATEGORIES
PROJECT CATEGORIES
SLOPES
(1)
A
B
C
D
Max. Slope
Max. Height
(m)
Max. Height
(m)
Max. Height
(m)
Max. Height
(m)
34°
unlimited
unlimited
unlimited
unlimited
45°
10
12
15
20
63°
3
4
5
6
PRS-NEOWEB VS. WALL TYPE CATEGORIES – DETAILED SUITABILITY
PRS-NEOWEB GEOCELL CATEGORIES
A
B
C
D
Max. Height
(m)
Max. Height
(m)
Max. Height
(m)
Max. Height
(m)
81°
84°
87°
unlimited
unlimited
unlimited
unlimited
3
x
unlimited
unlimited
unlimited
x
2
3
Base
x
Limited
Limited

Max. Slope
WALLS
(2)
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Rev. 13.01
* NOTES:
(1) SLOPES
 Cell height and size are according to design requirements, determined mainly by slope
inclination
 Topsoil infill, vegetated slopes
 Typical stake anchor: embedded depth=500 mm, diameter=10 mm
 Parameters are without tendons, which can be added for higher performance/heights.
 Stake anchor density [units/m2]: α≤34º: 1.0-1.2 | 34º<α≤45º: 1.2-1.5| 45º<α≤63º: 1.5-1.8:
Higher stake densities enable higher slopes for each category
 Non-woven geotextile under-layer (optional)
(2) RETAINING WALLS
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The above table is a general guide for the selection of PRS-Neoweb category only; and must
be confirmed by PRS/consultant engineer.
Based on typical cell size: PRS-445 (weld distance in mm) with granular infill
NOTE: THE ILLUSTRATIONS IN THIS DOCUMENT ARE EXAMPLES ONLY AND NOT
INTENDED FOR PLANNING, CONSTRUCTION , BIDDING, OR PERMIT PURPOSES .
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Rev. 13.01
VEGETATED SLOPE PROTECTION (A)
PRS-Neoweb Slope Cover Protection System
STABILITY
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Stable slope at natural state for desired inclination and height
INCLINATIONS

1:3 - 1:1 (18° - 45°)
HEIGHT

No limitation
SOLUTION
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Erosion control system
Green solution
Protects slope strength properties for long term stability
Easily installed on any changing/curved geometry
Enables efficient confined drainage system
INFILL
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Vegetated / locally excavated soil infill
ANCHORAGE

Metal / wood stakes + Neo-Clip
FEATURES
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Rev. 13.01
VEGETATED SLOPE PROTECTION (B)
PRS-Neoweb Slope Cover Protection System
STABILITY

Stable slope at natural state for desired inclination and
height
INCLINATIONS

1:3 - 2:1 (18° - 63°)
HEIGHT

Depends upon inclination, up to 15-25m
SOLUTION
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Erosion control system
Green solution
Protects slope strength properties for long term stability
Easily installed on any changing/curved geometry
Enables efficient confined drainage system
INFILL

Vegetated / locally excavated soil infill
ANCHORAGE
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Tendons + Neo-Clip™ holding cell walls
Tendons secured to deadman anchors at crest
FEATURES
PRS-EN-TD-ER-2001
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Rev. 13.01
GRAVITY RETAINING WALL
PRS-Neoweb Gravity Retaining Wall of Horizontal Layers
STABILITY
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Unstable slope at natural state for desired inclination / height
Slope requires earth retention structure to provide stability
INCLINATIONS

1:1 - 6:1 (45° - 81°)
HEIGHT

Typical range: 0.6 - 4.0m
SOLUTION
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Earth retention system
Erosion control system
Green solution
Flexible structure: retains its resistance after dynamic/seismic
actions, without cracking
Easily installed with curves to any longitudinal geometry
Enables efficient confined drainage system
Simultaneous construction of wall and fill embankment
Vegetated / locally excavated soil infill in first fascia cells
Granular soil for backfill and all other PRS-Neoweb cells
FEATURES
INFILL
PRS-EN-TD-ER-2001
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Rev. 13.01
REINFORCED RETAINING WALL
PRS-Neoweb Retaining Wall with Geogrid Reinforcement
STABILITY
INCLINATIONS
HEIGHT
SOLUTION
FEATURES
INFILL
PRS-EN-TD-ER-2001
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Unstable slope at natural state for desired inclination / height
Slope requires earth retention structure to provide stability
1:1.5 - 6:1 (34° - 81°)
Typical range: 3.0 - 12.0m
Earth retention system
Erosion control system
Green solution
Geogrid reinforcement
Flexible structure: retains its resistance after dynamic/seismic
actions, does not crack
Easily installed with curves at any longitudinal geometry
Enables efficient confined drainage system
Simultaneous construction of wall and fill embankment
Vegetated / locally excavated soil infill in first fascia cells
Granular soil for reinforced backfill and all PRS-Neoweb cells
11/16
Rev. 13.01
EARTH RETENTION & STABILIZED EROSION CONTROL
Combined PRS-Neoweb Gravity Retaining Wall & Back Slope Protection
STABILITY
INCLINATIONS
HEIGHT
SOLUTION
FEATURES
INFILL
ANCHORAGE
PRS-EN-TD-ER-2001
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Unstable slope at natural state for desired inclination and height
Slope requires earth retention structure to provide stability
Wall: 1:1 - 6:1 (45° - 81°)
Slope: 1:3 - 2:1 (18° - 63°)
Typical range for gravity wall: 0.6 - 4.0m
Typical range for reinforced wall: 3.0 - 12.0m
Slope: no limitation
Earth retention system
Erosion control system
Green solution
Protects slope strength properties for long term stability
Flexible structure: retains its resistance after dynamic/seismic
actions, does not crack
Easily installed with curves at any longitudinal geometry
Enables efficient confined drainage system
Vegetated / locally excavated soil infill in first fascia cells and in
back slope protection
Back slope anchorage system: metal stakes + Neo-Clip
12/16
Rev. 13.01
STEEP EARTH STABILIZATION
PRS-Neoweb Fascia Wall
STABILITY

Stable slope at natural state for desired inclination and height
INCLINATIONS

1:1 - 6:1 (45° - 81°)
HEIGHT





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

Typical range: 1.0 - 20.0m
Earth retention system
Erosion control system
Slope surface retention
Green solution
Flexible structure: retains its resistance after dynamic/seismic
actions, without cracking
Easily installed with curves at any longitudinal geometry
Enables efficient confined drainage system
Vegetated / locally excavated soil infill in first fascia cells
Granular soil for backfill and all other PRS-Neoweb cells

Tendons + NeoClip holding cell walls; tendons secured to anchors
SOLUTION
FEATURES
INFILL
ANCHORAGE
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Rev. 13.01
SOIL-NAILING HIGH & STEEP EARTH STABILIZATION
PRS-Neoweb Fascia Wall & Slope Stabilization & Soil-nailing
TABILITY
INCLINATIONS
SOLUTION
FEATURES
INFILL
ANCHORAGE
PRS-EN-TD-ER-2001
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Unstable slope with collapses/failures at natural state for desired
inclination and height
Slope requires earth retention structure to provide stability
1:1 - 6:1 (45° - 81°)
Provides Earth retention against collapses
Erosion control system
Slope surface retention
Green solution
Flexible structure: retains its resistance after dynamic/seismic
actions, without cracking
Easily installed with curves at any longitudinal geometry
Enables efficient confined drainage system
Vegetated / locally excavated soil infill in first fascia cells
Granular soil for backfill and all other PRS-Neoweb cells
Typical anchorage system: Soil-nailing, Tendons + Neo-Clip
holding cell walls; tendons secured to Soil-nailing
14/16
Rev. 13.01
REFERENCES
PRS-Neoweb for Earth Retention – Seismic Research (Leshchinsky, D., et al,
University of Delaware, USA)

Research and Innovation: Seismic Performance PRS-Neoweb Geocell Earth-retention Systems,
Geosynthetics, Leshchinsky, D. (2009).
Testing of PRS-Neoweb retention walls at the National Seismic Research Institute replicated a
severe earthquake. Seismic testing and analysis of PRS-Neoweb produced a very low seismic
reduction factor (coefficient). The Editors of Geosynthetics Magazine noted that “this article
departs from this policy in an effort to offer a guideline, an example, of how product
development for the geosynthetics industry can be done effectively. We hope these lessons can
further advance the geosynthetics industry into the 21st century with much success.”

Equivalent Seismic Coefficient in Geocell Retention Systems, Geotextiles and Geomembranes
Journal, Ling, H.I., Leshchinsky, et al (2009).
Results obtained from a large scale shake tables tests on reinforced geocell slopes are presented,
where PRS-Neoweb performed well under seismic loading, with Reduction Factors between 0.3
and 0.4 times PGA. Dr. Leshchinsky noted, however, that geocells made from HDPE are
unsuitable for long-term applications.

Seismic Response of Geocell Retaining Walls, Geotechnical & Geoenvironmental Engineering,
Ling, H.I., Leshchinsky, et al (2009).
Report on seismic response of PRS-Neoweb earth retention walls at the shake table National
Seismic Research Institute in Japan, to seismic activity similar to a severe earthquake, to
determine the failure mechanisms and PRS-Neoweb performance. Deformation was negligible
or within acceptable values and the walls remained stable.
Han, J., Xiaoming, Y., Leshchinsky, D., Parsons, R.L. (2007) “Behavior of Geocell-Reinforced Sand
Under a Vertical Load”, Submitted to Geosynthetics Committee (AFS70).
PRS-Neoweb Railway Embankment Testing (Leshchinsky, B., Ling, H., et al,
University of Columbia, USA)

Enhancing Ballast Performance using PRS-Neoweb Geocell Confinement, Geo-Frontiers 2011,,
Dallas, Leshchinsky, B., (2011)
The tests measured the strength and deformation behavior of Neoloy based PRS-Neoweb in 6
different embankment configurations. The results showed that PRS-Neoweb greatly restricted
vertical deformation by 40-72% and lateral displacement by 50-67% under loading. PRS-Neoweb
was stable under controlled cyclic loading within the stress amplitude of many transportation
applications (roadways, train, ballast, etc.).
Additional References
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
Gabr, M.A., Robinson, B., Collin, J.G., and Berg R.R., (2006) Promoting Geosynthetics Use on
Federal Lands Highway Projects, Federal Highway Administration, Central Federal Lands Highway
Division.
Han, J., Xiaoming, Y., Leshchinsky, D., Parsons, R.L. (2007) “Behavior of Geocell-Reinforced Sand
Under a Vertical Load”, Submitted to Geosynthetics Committee (AFS70).
Keller, G.K. (1995) "Experiences with Mechanically Stabilized Structures and Native Soil Backfill,"
Transportation Research Record No. 1474, Mechanically Stabilized Backfill and Properties of
Geosynthetics and Geocomposites, TRB, Washington, DC (November), 30-38.
Keller, G.K. (1995) "Experiences with Mechanically Stabilized Structures and Native Soil Backfill,"
Transportation Research Record No. 1474, Mechanically Stabilized Backfill and Properties of
Geosynthetics and Geocomposites, TRB, Washington, DC (November), 30-38.
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Koerner, R. M. (2005) Designing with geosynthetics, 5th Edition, Pearson/Prentice Hall, New
Jersey, USA.
Koerner, R. M. (2005) Designing with geosynthetics, 5th Edition, Pearson/Prentice Hall, New
Jersey, USA.
Leshchinksy, D., Ling, H.I., Wang, J-P., Rosen, A., Mohri, Y. (2009) “Equivalent Seismic Coefficient
in Geocell Retention Systems,” Geotextiles and Geomembranes Journal, No. 27, 9-18.
Ling, H.I., Leshchinsky, D., Wang, J.P., Mohri, Y. and Rosen, A. (2009) Seismic Response of Geocell
Retaining Walls: Experimental Studies”, Journal of Geotechnical and Geoenvironmental
Engineering, 135, No. 4, 516-524
Madhavi Latha, G., Rajagopal, K., and Krishnaswamy, N. R. (2006)“Experimental and Theoretical
Investigations on Geocell-Supported Embankments,” International Journal of Geomechanics, 6,
No. 1, 30-35
Madhavi Latha, G., Rajagopal, K., and Krishnaswamy, N. R. (2006)“Experimental and Theoretical
Investigations on Geocell-Supported Embankments,” International Journal of Geomechanics, 6,
No. 1, 30-35
Meyer, N. (2005) "Mechanical Behavior of Geocell Reinforced Soils ", Synthetic Materials in
Geotechnics, Congress, Technical University, CReport.
NHI – National Highway Institute (2001) Mechanically Stabilized Earth Walls & Reinforced Soil
Slopes Design & Construction Guidelines, US DOT, Publication No. FHWA-NHI-00-043, March
Pokharel, S.K. , Han J., Leshchinsky, D., Parsons, R.L. and Halahmi, I. (2008) “Experimental
Evaluation of Influence Factors for Single Geocell-Reinforced Sand, Submitted to Geosynthetics
Committee (AFS70).
Rajagopal, K., Krishnaswamy, N.R. and Madhavi Latha, G. (1999) “Behavior of Sand Confined with
Single and Multiple Geocells,” Journal of Geotextiles and Geomembranes, 17, No. 3, 171-184.
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