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

Chapter 2—Overview of Geosynthetics for Use in Embankment Dams2.8 GeocompositesGeocomposites (figs. 2.11 through 2.19) are made by bonding together two or morelayers of flexible synthetic materials that perform different functions. According tothe ASTM (2005) definition, a geocomposite is “a product composed of two or morematerials, at least one of which is a geosynthetic”. There are a myriad ofgeocomposites, some of which have already been alluded to in the above discussions.The following are illustrative examples:• Geomembrane/Geotextile Composite• Geonet/Geotextile Composite• Geogrid/Geotextile Composite• Geomat/Geotextile CompositeAn example of a specific drainage geocomposite would be a “wick drain” which iscomprised of a 4 inch (100 mm) wide waffle like corrugated structure surrounded bya filter geotextile. Geocomposites are the fastest growing segment of geosyntheticswhen considering the number of products. Most geocomposites are associated withthe erosion control industry and incorporate both synthetic mats and geotextiles withnatural materials.Figure 2.11.—Photograph of a single-sided geocomposite geomembrane. It is made bybonding a geotextile (grey colored layer) to one side of a geomembrane.29