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 FORWARD SCOPE OF THIS DOCUMENT PRS INTRODUCTION SLOPES EARTH RETENTION DURABILITY SUSTAINABLE SOLUTION EXAMPLES OF NEOWEB EARTH STABILIZATION SOLUTIONS VEGETATED SLOPE PROTECTION (A) Neoweb Slope Cover Protection System, Expanded Downslope VEGETATED SLOPE PROTECTION (B) Neoweb Slope Cover Protection System, Expanded Downslope GRAVITY RETAINING WALL Neoweb Gravity Retaining Wall of Horizontal Layers 200 mm Depth REINFORCED RETAINING WALL Neoweb Reinforced Retaining Wall of Horizontal Layers 200 mm Depth 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 Earth Stabilization Overview 2/14 PRS proprietary 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 Earth Stabilization Overview 3/14 PRS proprietary 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: 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 Earth Stabilization Overview 4/14 PRS proprietary 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: 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 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 – – – Multi-grade transportation arteries Green road and rail embankments Safety barriers Rehabilitation – – Mine site and quarry restoration Failed slopes Environmental – – Energy and noise absorbers Green walls Channels and Coastlines – – 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 Earth Stabilization Overview 5/14 PRS proprietary 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 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 Earth Stabilization Overview 6/14 PRS proprietary 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 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 Earth Stabilization Overview 7/14 PRS proprietary 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 Earth Stabilization Overview 8/14 PRS proprietary REINFORCED RETAINING WALL Neoweb Reinforced Retaining Wall of Horizontal Layers 200 mm Depth STABILITY INCLINATIONS HEIGHT SOLUTION FEATURES INFILL Earth Stabilization Overview 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 9/14 PRS proprietary REINFORCED SLOPE & EROSION CONTROL Neoweb Stabilized Reinforced Slope and Slope Cover Protection System, Expanded Downslope STABILITY INCLINATIONS HEIGHT SOLUTION FEATURES INFILL ANCHORAGE 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 10/14 PRS proprietary EARTH RETENTION & STABILIZED EROSION CONTROL Combined Neoweb Gravity Retaining Wall and Back Slope Cover Protection System STABILITY INCLINATIONS HEIGHT SOLUTION FEATURES INFILL 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 11/14 PRS proprietary 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 Earth Stabilization Overview 12/14 PRS proprietary 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 Earth Stabilization Overview 13/14 PRS proprietary 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 NR M L G B “ C Journal of Geotextiles and Geomembranes, 17, No 3, 171-184 14/14 PRS proprietary