Introduction to Cellular Geosynthetics (Geofoams and Geocombs) A Manhattan College Center for Geotechnology Technology Transfer through Distance Learning Program Educational Product Presentation prepared by John S. Horvath, Ph.D., P.E. Professor of Civil Engineering Director/Center for Geotechnology Manhattan College School of Engineering Bronx, New York, U.S.A. © 3 September 2001 by John S. Horvath. All rights reserved.

Manhattan College · School of Engineering · Center for Geotechnology Construction Material Changes improvements to traditional materials (steel and PCC) development of new functions (roles) and applications for existing materials development of new materials use of recycled waste materials 02 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Construction Material Changes improvements to traditional materials (steel and PCC) development of new functions (roles) and applications for existing materials <<< geocombs and some geofoams development of new materials <<< some geofoams use of recycled waste materials <<< some geofoams 03 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Geofoam ... Generic term for any closed-cell foam used in a geotechnical application that is manufactured either in a fixed plant or in-situ from an expansion process using a blowing agent: polymeric (plastic) polyethylene (PE) expanded polystyrene (EPS) <<< predominant extruded polystyrene (XPS) polyurethane (PUR) glass (cellular glass) cementitious 04 Manhattan College · School of Engineering · Center for Geotechnology

EPS block in temporary storage after molding. The entire block weighs less than the person handling it! 05 Manhattan College · School of Engineering · Center for Geotechnology

Example of one of at least three different designs of EPS-shape geofoam "anti-buoyancy" blocks developed in Japan (dimensions in millimetres). 06 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Geocomb ... … the newest "geo" material (geosynthetic), formerly referred to as "structures alveolaires ultra légères" (SAUL) or "ultra light cellular structures" (ULCS) in France where it was developed and has been used since the 1980s. … defined as an open-cell (honeycomb shaped in cross-section) polymeric (PP, PVC) material created by an extrusion process. Typically supplied as a panel- or block-shaped final product. 07 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology typical tube (~ 25 mm/1 in) PP (left) and PVC (right) geocombs. 08 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Benefits of Using Geofoams and Geocombs efficient use of solid material work with the forces of nature, not against them can be useful for both new construction and with existing structures, permanent and temporary, all climates/weather, "good" and "poor" ground provide unique geosynthetic functions can be multifunctional in many applications compatible and synergistic with other types of geosynthetics 09 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Overview of Design Process design by function to identify desired properties define parameters for desired analyses and obtain relevant technical information for these parameters generally treat as an equivalent earth material and use conventional geotechnical analytical methods economic assessment (construction + O&M) relevant standards and specifications 10 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Geosynthetic Functions thermal insulation (1960s) >>> geofoams only lightweight fill (1970s) >>> geofoams & geocombs drainage (1970s) >>> geofoams & geocombs noise/vibration damping (1980s) >>> geofoams only compressible inclusion (1980s) >>> geofoams only structural (1990s) >>> geofoams only 11 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Important Aspects of Material Behavior and Other Technical Issues for Design index properties mechanical (stress-strain-time) behavior thermal properties constructability and safety durability environmental impact 12 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Factors to Consider in an Economic Assessment design aspects of initial construction constructability aspects of initial construction reduced costs of operation and maintenance 13 Manhattan College · School of Engineering · Center for Geotechnology

Standards and Specifications standards constitute technology documentation and are the foundation of any technology specifications are the project-specific application of relevant standards to define the minimum acceptable results in a given application 14 Manhattan College · School of Engineering · Center for Geotechnology Manhattan College · School of Engineering · Center for Geotechnology

Thermal Insulation Benefits life-cycle energy cost savings construction cost savings improved geotechnical/structural performance 15 Manhattan College · School of Engineering · Center for Geotechnology Manhattan College · School of Engineering · Center for Geotechnology

Thermal Insulation Applications buildings and storage tanks (all climates) landfill liners (all climates) shallow buried structures (all climates) earth retaining structures (cold climates) pavements and railways (cold climates) underground conduits (cold climates) shallow foundations (cold climates) 16 Manhattan College · School of Engineering · Center for Geotechnology Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Test of landfill-liner thermal insulation alternatives in the U.S.A. 17 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology geofoam drainage layer Use of geofoam behind an earth retaining structure to prevent seasonal freezing of the wall drainage system and retained soil. Note that the drainage system could be incorporated into the geofoam product for overall increased efficiency and reduced cost. 18 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Rebuilding an existing road in Norway with geofoam insulation. 19 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Rebuilding an existing railway in Norway with geofoam insulation. 20 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology geofoam depth of seasonal freezing normal conduit depth Use of geofoam above an underground conduit to locally modify the depth of seasonal freezing to allow shallower conduit embedment. Note that the geofoam could also be designed to act as a compressible inclusion to reduce forces acting on the conduit. 21 Manhattan College · School of Engineering · Center for Geotechnology

Typical Frost Protected Shallow Foundation concept application. 22 geofoam depth of seasonal freezing footing depth without insulation Typical Frost Protected Shallow Foundation concept application. 22 Manhattan College · School of Engineering · Center for Geotechnology

Lightweight Fill Applications embankments and fills: transportation water resources foundation support architecture and landscaping earth retaining structure backfill and fills 23 Manhattan College · School of Engineering · Center for Geotechnology Manhattan College · School of Engineering · Center for Geotechnology

Rebuilding a failed road embankment in the U.S.A. in the winter using EPS-block geofoam. 24 Manhattan College · School of Engineering · Center for Geotechnology

Spraying a PCC facing on a "geofoam wall" type road fill in the mountains of Japan. 25 Manhattan College · School of Engineering · Center for Geotechnology

Constructing an EPS-block geofoam road embankment in Norway for a combined bridge approach fill and bridge abutment foundation. Note the wooden formwork for the abutment footing. 26 Manhattan College · School of Engineering · Center for Geotechnology

Using EPS-block geofoam to construct an abutment backfill for a new road bridge in Chile. 27 Manhattan College · School of Engineering · Center for Geotechnology

Completed approach embankment and abutment backfill using EPS-block geofoam for a new road bridge in Canada. 28 Manhattan College · School of Engineering · Center for Geotechnology

Constructing an approach embankment and abutment backfill using geocomb blocks for a road bridge in France. 29 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Rehabilitating and raising a levee in the U.S.A. using EPS-block geofoam. 30 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Building basement wall in the U.S.A. backfilled using EPS-block geofoam. 31 Manhattan College · School of Engineering · Center for Geotechnology

Anchored bulkhead in Japan partially backfilled using EPS-block geofoam. 32 Manhattan College · School of Engineering · Center for Geotechnology

Barbed connector plates used between blocks of EPS geofoam in Japan (dimensions are in millimetres, 25 mm = 1 in). 33 Manhattan College · School of Engineering · Center for Geotechnology

100 mm (4 in) square barbed connector plate used between blocks of EPS geofoam in the U.S.A. 34 Manhattan College · School of Engineering · Center for Geotechnology

Drainage Applications fluid transmission using geofoams: ground water around below-grade structures ground water behind earth retaining structures leachate collection systems in landfills ground-borne gases around below-grade structures fluid transmission and storage using geocombs 35 Manhattan College · School of Engineering · Center for Geotechnology Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology EPS-shape geofoam product developed in the U.K. specifically for collecting and draining ground-borne gases such as methane and radon. Note that it also provides thermal insulation for the structure. 36 Manhattan College · School of Engineering · Center for Geotechnology

Geofoam drainage geocomposite available in Asia, Europe and the glued polystyrene porous block high-permeability core Geofoam drainage geocomposite available in Asia, Europe and the U.S.A. that uses a glued polystyrene porous block core. 37 Manhattan College · School of Engineering · Center for Geotechnology

Geofoam sheet-drain product composed of pieces of recycled PE that was developed in The Netherlands. 38 Manhattan College · School of Engineering · Center for Geotechnology

Drainage (fluid transmission and storage) applications using geocomb panels and blocks developed in France. 39 Manhattan College · School of Engineering · Center for Geotechnology

Noise and Vibration Damping Applications attenuation of small-amplitude, ground-borne vibrations from: motor vehicles trains attenuation of noise from trains 40 Manhattan College · School of Engineering · Center for Geotechnology Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology EPS-block geofoam PCC slab EPS-block geofoam EPS-block geofoam used to dampen noise and vibrations from a railway in Germany . The EPS blocks directly beneath the tracks are also acting as a lightweight fill for the clay ("Ton") subgrade. 41 Manhattan College · School of Engineering · Center for Geotechnology

EPS-block geofoam used to dampen noise and vibrations PCC ties (sleepers) PCC layers EPS-block geofoam used to dampen noise and vibrations from light-rail vehicles (trams/trolleys) in France and Germany. 42 Manhattan College · School of Engineering · Center for Geotechnology

Compressible Inclusion Applications lateral earth pressure and settlement reduction: shear-strength mobilization of "normal" soils volume change of expansive/freezing soil/rock structure movement vertical stress reduction from expansive soil/rock vertical arching above underground conduits 43 Manhattan College · School of Engineering · Center for Geotechnology Manhattan College · School of Engineering · Center for Geotechnology

tensile reinforcement (optional) geofoam soil movement tensile reinforcement (optional) Use of geofoam compressible inclusion behind a rigid/non-yielding earth retaining structure to reduce lateral earth pressures (optional use of geosynthetic tensile reinforcement also shown). 44 Manhattan College · School of Engineering · Center for Geotechnology

Use of a resilient-EPS geofoam geocomposite in the U.S.A. to act as a compressible inclusion to accommodate integral-abutment bridge movement. Drainage is also provided by the same product. 45 Manhattan College · School of Engineering · Center for Geotechnology

Use of a geofoam compressible inclusion around ground movement ground movement ground movement Use of a geofoam compressible inclusion around foundation elements of a structure to reduce stresses in expansive ground (soil or rock) conditions. 46 Manhattan College · School of Engineering · Center for Geotechnology

EPS-block geofoam used as a compressible inclusion around a reinforced-PCC grade beam in expansive soil in the U.K. (geofoam also served as formwork during construction). 47 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology EPS-block geofoam used as a compressible inclusion beneath a deep-foundation supported tunnel base slab in expansive ground in the U.K. 48 Manhattan College · School of Engineering · Center for Geotechnology

EPS-block geofoam product used as a compressible inclusion beneath a deep-foundation supported base slab of a building in Canada (similar product also developed in U.K.). 49 Manhattan College · School of Engineering · Center for Geotechnology

Use of a geofoam compressible inclusion above an ground movement ground movement Use of a geofoam compressible inclusion above an underground conduit to reduce vertical stresses acting on the conduit by inducing vertical arching within the overlying soil. 50 Manhattan College · School of Engineering · Center for Geotechnology

Multifunctional use of a geofoam geocomposite only ~ 150 mm (6 in) thick simultaneously providing compressible inclusion, drainage and thermal insulation behind a building basement wall in the U.S.A. 51 Manhattan College · School of Engineering · Center for Geotechnology

Structural/Miscellaneous Applications forms for PCC walls MSEW facing panels void formers for PCC slabs crash barriers for motor vehicles and aircraft impact cushioning for rock sheds void filling and foundation remediation 52 Manhattan College · School of Engineering · Center for Geotechnology Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology Panels cut from block-molded EPS used as formwork for a reinforced-PCC basement wall in the U.S.A. The EPS also provides post-construction thermal insulation for the life of the structure. 53 Manhattan College · School of Engineering · Center for Geotechnology

MSEW system developed in the U.K. with geogrid reinforcement and facing panels cut from block-molded EPS. 54 Manhattan College · School of Engineering · Center for Geotechnology

Generic components of EIFS technology used over EPS and XPS two-part stucco-like finish EPS mesh reinforcement underlayment Generic components of EIFS technology used over EPS and XPS to create a wide variety of durable architectural finishes. 55 Manhattan College · School of Engineering · Center for Geotechnology

Block-molded EPS used as a lightweight void former for a pile-supported structural slab constructed over a soft subgrade in the U.S.A. 56 Manhattan College · School of Engineering · Center for Geotechnology

Manhattan College · School of Engineering · Center for Geotechnology EPS blocks Credit: Paul Arch Racing Photos EPS blocks used as crash-cushioning barriers around an auto-racing track in the U.S.A. Note evidence of extensive prior collision damage. 57 Manhattan College · School of Engineering · Center for Geotechnology

EPS blocks used as protection for PCC rock sheds in mountainous areas in Europe and Japan. 58 Manhattan College · School of Engineering · Center for Geotechnology