Geotextiles in Embankment Dams - Association of State Dam Safety ...

Chapter 2—Overview of Geosynthetics for Use in Embankment Dams• Ethylene-Propylene Diene Monomer (EPDM)• Ethylene Interpolymer Allowy (EIA)• Chlorosulfonated Polyethylene (CSPE)• Flexible Polypropylene (fPP)In addition to traditional polymeric geomembranes, there are also bituminousgeomembranes that are manufactured in a plant by impregnating or coating a fabricwith bitumen or a polymer/bitumen blend. These are referred to as PrefabricatedBituminous Geomembranes (PBGM).All of the above have or are being used as a waterproofing element in damconstruction which is the largest functional use of geosynthetics in dam constructionand rehabilitation. As mentioned previously, the first use of a geosynthetic in damconstruction was on the Contrada Sabetta Dam in Italy in 1959 and the use was as awaterproofing element on the upstream face which is still in operation today afterover 45 years of service (Cazzuffi, 1987).In addition to the base polymer for which the geomembrane is named, allgeomembranes contain additives which perform myriad functions. The additivesrange from simple carbon black (for UV protection) to complicated antioxidantpackages used to reduce the effects of oxidation on aging.21