NEOWE EARTH STABILIZATION

NEOWEB™
EARTH
STABILIZATION

June 2009
Ver. 6.2a

TECHNICAL OVERVIEW

© 2009 Copyright 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. PRS confidential and proprietary.


Contents
NEOWEB CELLULAR CONFINEMENT SYSTEM........................................................................................... 3
FORWARD .............................................................................................................................................. 3
SCOPE OF THIS DOCUMENT .................................................................................................................. 3
PRS ......................................................................................................................................................... 3
INTRODUCTION ........................................................................................................................................ 4
SLOPES ................................................................................................................................................... 4
EARTH RETENTION................................................................................................................................. 4
DURABILITY ............................................................................................................................................ 4
SUSTAINABLE SOLUTION ....................................................................................................................... 5
EXAMPLES OF NEOWEB EARTH STABILIZATION SOLUTIONS ................................................................ 5
VEGETATED SLOPE PROTECTION (A) ........................................................................................................ 6
Neoweb Slope Cover Protection System, Expanded Downslope .......................................................... 6
VEGETATED SLOPE PROTECTION (B) ........................................................................................................ 7
Neoweb Slope Cover Protection System, Expanded Downslope .......................................................... 7
GRAVITY RETAINING WALL ...................................................................................................................... 8
Neoweb Gravity Retaining Wall of Horizontal Layers 200 mm Depth ................................................. 8

REINFORCED RETAINING WALL ................................................................................................................ 9
Neoweb Reinforced Retaining Wall of Horizontal Layers 200 mm Depth ............................................ 9
REINFORCED SLOPE & EROSION CONTROL ............................................................................................ 10
Neoweb Stabilized Reinforced Slope and Slope Cover Protection System, Expanded Downslope .... 10
EARTH RETENTION & STABILIZED EROSION CONTROL ............................................................................... 11
Combined Neoweb Gravity Retaining Wall and Back Slope Cover Protection System ....................... 11
STEEP EARTH STABILIZATION ................................................................................................................. 12
Neoweb Fascia Wall............................................................................................................................. 12
SOIL-NAILING HIGH & STEEP EARTH STABILIZATION ............................................................................. 13
Neoweb Fascia Wall & Slope Stabilization using Soil-nailing .............................................................. 13
REFERENCES ........................................................................................................................................... 14

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NEOWEB CELLULAR CONFINEMENT SYSTEM
FORWARD
T N
“
manufactured and marketed by PRS, comprised of three-dimensional, perforated and textured
honeycombed geocells. 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.

SCOPE OF THIS DOCUMENT
This document describes and illustrates typical earth stabilization strategies available from PRS,

which depend upon the angle and degree of stabilization and reinforcement required, infill type,
surface cover and application use.

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 40 countries worldwide.

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INTRODUCTION
SLOPES
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 Neoweb prevents downslope movement from hydrodynamic and
gravitational forces. 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 Neoweb system tolerates high sheet-flow conditions and prevents channeling by limiting flow
and increasing hydraulic shear stresses. Neoweb slope protection is also applicable to Channel
Protection. 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. 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 Neoweb system layers maintain
structural stability, even in compressible and unstable foundation subgrades.

DURABILITY
Neoweb is comprised of advanced polymeric alloys that make the cellular confinement system stiff,
flexible and durable. In particular the Neoweb patent-pending 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 Neoweb earth retention structures. In addition, Neoweb is non-degradable
and is resistant to weathering, extreme temperatures and water, which can affect concrete, steel and
timber solutions.

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SUSTAINABLE SOLUTION
Neoweb is the best-available sustainable solution for long-term soil protection and stabilization in
slopes, embankments and retaining walls. 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 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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
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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.

EXAMPLES OF 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

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Transportation and construction
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Multi-grade transportation arteries
Green road and rail embankments
Safety barriers

Rehabilitation
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Mine site and quarry restoration
Failed slopes

Environmental
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Energy and noise absorbers
Green walls

Channels and Coastlines
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Storm water structures
Coastal cliff preservation

Site grading
–
–

Expanding fields and yards
Grading site to boundaries

NOTE: THE ILLUSTRATIONS IN THIS DOCUMENT ARE EXAMPLES ONLY AND NOT INTENDED FOR PLANNING ,
CONSTRUCTION , BIDDING , OR PERMIT PURPOSES .

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VEGETATED SLOPE PROTECTION (A)
Neoweb Slope Cover Protection System, Expanded
Downslope

STABILITY



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



Vegetated / locally excavated soil infill

ANCHORAGE



Metal / wood stakes + Neo-Clip

FEATURES

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VEGETATED SLOPE PROTECTION (B)
Neoweb Slope Cover Protection System, Expanded
Downslope

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




Tendons + Neo-Clip™ holding cell walls
Tendons secured to deadman anchors at crest

FEATURES

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GRAVITY RETAINING WALL
Neoweb Gravity Retaining Wall of Horizontal Layers
200 mm Depth




Unstable slope at natural state for desired inclination and
height
Slope requires earth retention structure to provide stability

INCLINATIONS



1:1 - 6:1 (45° - 81°)

HEIGHT



Typical range: 0.6 - 4.0m

SOLUTION






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 required 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 Neoweb cells

STABILITY

FEATURES



INFILL

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REINFORCED RETAINING WALL
Neoweb Reinforced Retaining Wall of Horizontal Layers
200 mm Depth

STABILITY

INCLINATIONS
HEIGHT
SOLUTION

FEATURES

INFILL

Earth Stabilization Overview

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Unstable slope at natural state for desired inclination and
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
Unique reinforcement of three-dimensional Neoweb system
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 other Neoweb
fascia and reinforcement cells

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REINFORCED SLOPE & EROSION CONTROL
Neoweb Stabilized Reinforced Slope and Slope Cover
Protection System, Expanded Downslope

STABILITY

INCLINATIONS
HEIGHT
SOLUTION

FEATURES

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
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



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

INFILL

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ANCHORAGE

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Earth Stabilization Overview

Unstable slope at natural state for desired inclination and
height
Slope requires earth retention structure to provide stability
1:2 – 2:1 (27° - 63°)
Typical range: 2.0 - 12.0m
Earth retention system
Erosion control system
Green solution
Unique reinforcement of three-dimensional Neoweb system
Flexible structure: retains its resistance after dynamic/seismic
actions, without cracking

Easily installed with curves at any longitudinal geometry
Enables efficient confined drainage system
Simultaneous construction of Neoweb structure and
embankment
Vegetated / locally excavated soil infill for exposed slope
Granular soil for reinforced backfill and Neoweb
reinforcement
Metal / wood stakes + Neo-Clip for slope protection system

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EARTH RETENTION & STABILIZED EROSION CONTROL
Combined Neoweb Gravity Retaining Wall and Back Slope
Cover Protection System

STABILITY
INCLINATIONS
HEIGHT

SOLUTION

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




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

FEATURES

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INFILL

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

ANCHORAGE



Earth Stabilization Overview

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
The wall and slope can be 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

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STEEP EARTH STABILIZATION
Neoweb Fascia Wall

STABILITY



Stable slope at natural state for desired inclination and height

INCLINATIONS



1:1 - 6:1 (45° - 81°)

HEIGHT








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 Neoweb cells
Tendons + Neo-Clip holding cell walls; tendons secured to stake
anchors

SOLUTION

FEATURES

INFILL

ANCHORAGE





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SOIL-NAILING HIGH & STEEP EARTH STABILIZATION
Neoweb Fascia Wall & Slope Stabilization using Soil-nailing




Unstable slope with collapses/failures at natural state for desired
inclination and height
Slope requires earth retention structure to provide stability

INCLINATIONS



1:1 - 6:1 (45° - 81°)

SOLUTION







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 Neoweb cells
Typical anchorage system: Soil-nailing, Tendons + Neo-Clip
holding cell walls; tendons secured to Soil-nailing

STABILITY

FEATURES

INFILL
ANCHORAGE

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REFERENCES
H
U

J X
V

Y L
L

D P
RL
B
G ocell-Reinforced Sand
Submitted to Geosynthetics Committee (AFS70).

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.

Elias, V., Christopher, B.R., Berg, R.R. (2001) Mechanically Stabilized Earth Walls and Reinforced Soil
Slopes Design and Construction Guidelines, National Highway Institute, Federal Highway
Administration, U.S. Department of Transportation, Washington, D.C
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.
Koerner, R. M. (2005) Designing with Geosynthetics, 5th Edition, Pearson/Prentice Hall, New Jersey,
USA.
Leshchinksy, D.
retention Syst

Research and Innovation: Seismic Performance of Various Geocell EarthGeosysnthetics, No. 27, No. 4, 46-52.

Leshchinksy, D., Ling, H.I., Wang, J-P., Rosen, A., Mohri, Y. (2009) Equivalent Seismic Coefficient in
G
R
“
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
R
W
E
“
Journal of Geotechnical and Geoenvironmental Engineering,
135, No. 4, 516-524
Madhavi Latha, G., Rajagopal, K., and Krishnaswamy, N. R. (2006) E
T
Investigations on Geocell-“
E
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.
Pokharel, S.K. , Han J., Leshchinsky, D., Parsons, R.L. and H
I
E
E
of Influence Factors for Single Geocell-Reinforced Sand, Submitted to Geosynthetics Committee
(AFS70).
R
“

K K
M

G

Earth Stabilization Overview

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M
L
G
B
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C
Journal of Geotextiles and Geomembranes, 17, No. 3, 171-184.

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