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

Chapter 3Functions of Geotextiles in Embankment DamsGeotextiles have been used in many applications as components in the design andconstruction of embankment dams. These products have been used more frequentlyin repair of existing dams where dam safety concerns mandate rapid construction. Inthe construction of new dams, particularly in the United States, geotextiles areusually a secondary or composite component in combination with natural materials.Geotextiles have been substituted for natural materials in dams by some practitionerswhen the availability or expense of natural aggregates makes them impractical.Geotextiles have been considered for the following functions in various designapplications associated with dams:• Filtration• Drainage Conveyance• Separation• Protection• Reinforcement• Surface Erosion ControlGeotextiles have been used more frequently as a separator function for drainageaggregates or riprap and far less frequently as traditional filter/drainage applicationsin dams. Another common application is in soil reinforcement or to improve theslope stability of an embankment.3.1 Filtration and drainageIn a limited number of cases, geotextiles have been used in the filtration of seepagethrough and under embankment dams (fig. 3.1). These materials, when properlydesigned and constructed, can act as a filter, controlling the migration or thetransport of soil particles by seepage (Holtz, Christopher, and Berg, 1997). However,55