INTERLOCK BETWEEN PARTICLES AT EACH PERFORATION

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1 for Storm Water Management RUN OFF CONTROLS Porous Parking & Vehicle Access Cellular Confinement Systems (CCS) A Cellular Confinement System (CCS) is an engineered, expandable, polyethylene, honeycomb-like cellular structure. CCS cells and panels are available various sizes. CCS cells and panels are available various heights. 8 Small Cell 6 Medium Cell Large Cell 4 3 Width - 10 Cells Width - 8 Cells Width - 5 Cells CCS Cell Properties: Perforated Cell Walls. CCS Cell Properties: Perforated Cell Walls. INTERLOCK BETWEEN PARTICLES AT EACH PERFORATION 10 mm DIAMETER HOLES (TYPICAL) 10 mm DIAMETER HOLES (TYPICAL) PERFORATED CELL WALL ENHANCED LOAD TRANSFER BETWEEN CELL WALL AND INFILL PERFORATED CELL WALL CROSS CELL FLOW OF WATER AND NUTRIANTS 1

2 CCS Cell Properties: Perforated Cell Walls. CCS Cell Properties: Textured Surface A A OPTIMUM CELL WALL / INFILL INTERFACE FRICTION 10 mm DIAMETER HOLES (TYPICAL) CROSS CELL GRASS ROOT LOCK-UP SECTION A-A TEXTURED CELL WALL SURFACE TEXTURED CELL WALL PERFORATED CELL WALL Palletized CCS is delivered to project sites. The CCS is expanded and then installed. Cellular Confinement Systems (CCS) Components Tendons Kevlar High Strength Polyester Polypropylene Special devices CCS Components Anchors 2

3 CCS Components: Staples & Stapling devices Infill options for the Topsoil Infill CCS include free draining soil, sand, stone, concrete or mixtures of soil with sand and/or stone. Geosynthetics: ECBs & TRMs / Geotextiles / Grids / Geomembranes The CCS structure will enhance the performance of any infill materials. CCS Applications Load Support Shear Surface CCS Load Distribution A CCS in a load support application is a multi-component, engineered system consisting of: Virtually all manufacturers offer basic design guidance, some offer preliminary evaluations. A specifically sized geocell (cell area and depth). A geosynthetic separation layer between the in-situ soils and the structural infill materials when those materials are different from each other (this layer is not needed when the underlying soil type and the infill material are the same). A structural infill material which is placed and compacted in the cell. 3

4 Virtually all manufacturers offer basic design guidance, some offer preliminary evaluations. Virtually all manufacturers offer basic design guidance, some offer preliminary evaluations. Virtually all manufacturers offer basic design guidance, some offer preliminary evaluations. CCS Gravel parking: Site is prepared. CCS panels are expanded and stapled. Infill is placed onto expanded CCS. 4

5 Infill is spread and compacted into CCS. Completed CCS Gravel parking Application. Comparison of CCS gravel parking area vs conventional gravel lot during a rain event. Steep Access Road / Surface Stability Application / April 2003 Unexpanded, palletized CCS panels on site. Grade surface and cut termination trenches. Pa. American Water Co. / West Decatur, PA Water Tank 5

6 Finish grade road / install geotextile fabric Pre-attach panels before expanding into place Expand panels and anchor in place. Filling cells with a 2A stone w/ 2 wearing surface Some hand work may be needed to finishgrade surface. Finished installation 6

7 Steel Structures Industrial Yard Rutting of unconfined gravel caused costly maintenance problems for both the yard and equipment AGGREGATE BASE SUBGRADE UNCONFINED GRANULAR PAVEMENT SYSTEM The engineered solution called for a combination of Cellular Confinement and Geotextile a specific section was designed based on loads, numbers of passes, etc SURFACE CCS SECTION INFILL SUBBASE GEOTEXTILE SUBGRADE Subgrade Cellular Confinement panel is held open with sand bags. Geotextile Sub-base CCS Panels stapled together and ready for in-fill 7

8 Panels are easily fit around protrusions. In-filling Cellular Confinement with stone. More panels are staged as construction continues CCS stone infill is compacted with standard equipment. Large section of stone filled Cellular Confinement. Section completed adjacent to curb 8

9 Field testing completed CCS application. Field testing completed CCS application. Field testing completed CCS application. Field testing completed CCS application. SURFACE GEOWEB SECTION AGGREGATE SUBBASE SUBGRADE THE GEOWEB GRANULAR PAVEMENT SYSTEM CCS filled with stone can provide a cost effective and easy to construct pervious roadside treatment. MPSS WQI USD GCLs PP&VA WMPP PPPS CCS SC EP SS Filling CCS with stone and soil mixture will facilitate final turf surface. < Home 9

10 Filling CCS with stone and soil mixture will facilitate final turf surface. CCS Pavement Base Rehabilitation CCS Load Distribution Stream Crossing Heavy duty industrial use facility Heavy duty industrial use facility CCS Load Distribution: Road over Soft Soils. 10

11 CCS LS Applications and Concepts Supported CCS Load Distribution: Temporary Road over Soft Soils. The CCS as a load support system can be used in a wide variety of applications: Load support systems over non-supportive soils, Surface stabilization of unstable aggregates areas (parking lots and roadsides), Stabilization of road bases to reduce site disturbance and provide greater pavement life, Vegetated load support systems (parking and emergency access areas). CCS LS Applications and Concepts Supported A CCS can support the non-structural and structural BMPs listed below: Protect/utilize natural flow pathways in overall stormwater planning and design Minimize soil compaction in disturbed areas Reduce Impervious Cover Reduce Street Imperviousness Reduce parking Imperviousness Runoff Volume / Infiltration based Vegetative and soil based Vegetated Filter Strips Porous pavement with infiltration beds CCS Key Benefits The CCS provides the following benefits: In-filled can be stone or soil for permeable paving/parking applications Reduction in depth of engineered base requirements leading to reduced site disturbance The CCS can be rapidly placed to provide immediate load support. H Key Design Elements The CCS for load support uses the following elements: a geosynthetic separation layer, may be: *non-woven geotextile for soil type separation, *woven geotextile for reinforcement and soil type separation, an appropriately sized geocell section: *small or medium cell size *4, 6, 8, 9.5 inch depth cell infill materials(s), may be: *aggregate *aggregate / topsoil blend H H Key Design Considerations Key design considerations in determining which of proper selection of, and design with, the components will be as follows: Stone versus vegetated infill. If a vegetated solution is desired access time and sustainability of turf have to be considered (traffic may have to be kept off the CCS to facilitate healthy establishment of the vegetated infill). Vehicle loads and frequency of will play a significant role in proper selection and design of a CCS load support project. H 11

12 Preconstruction checklist (site walk-through check list) Prior to construction, check: Post construction inspection checklist During and after construction, check: Site grading plan Presence of CCS materials Geotextile separation layer if required Geocell materials Infill, if other than from site excavations Presence of installation tools Presence of installation instructions Presence of qualified manufacturers representative if required Is grade and elevation as specified Has the separation layer been placed Are the geocell sections expanded correctly infilled with the specified infill is infill compacted to specification If vegetated, are the appropriate seed and nutrients applied H H 12