Reinforced Slopes Using Geotextile - Fibers Composite

Paper on file with ASDSO.

Planar geosynthetics such as high-strength geotextiles and geogrids have been in widespread use as earth slope reinforcement for more than a decade. The use of these materials in slope applications has been highly successful. Common practice has been to provide primary reinforcement in discrete layers throughout the reinforced zone, with shorter, intermittent layers of the planar reinforcement placed between the primary layers at the slope face to act as secondary reinforcement. The primary reinforcement provides overall stability, while the intended purpose of the secondary reinforcement is to reduce raveling and mini­failures of the slope face between the primary reinforcement layers. However, in many cases the secondary reinforcement does not effectively reduce the raveling and mini-failures long term. This has resulted in significantly increased maintenance costs on many projects. Until recently, no viable solution for this problem was available. Within the past seven years, short geosynthetic fibers ( Geofibers have been successfully used on more than 25 slope projects in the United States. These projects have involved repairs of shallow slope failures, repair of deep­seated slope failures, and veneer reinforcement in new slope construction to reduce future maintenance costs. These fibers also have tremendous potential for use as veneer and secondary reinforcement in geotextile - fibers composite reinforcement of slopes. This combination of geosynthetics has the potential to virtually eliminate any significant future maintenance problems due to raveling and mini-failures at the slope face, for properly designed reinforced embankments. Brief case histories of slopes constructed using fiber-reinforced soil, and design examples using high-strength geotextile - fibers composite are discussed.