Application of Anchored Geosynthetic Systems for In Situ Slope Stabilization of Fine-Grained Soils

Abstract

The use of anchored geosynthetic systems (AGS) was proposed by Koerner et al. for the stabilization of slopes at or near their failure state. AGS provides in-situ stabilization of soil slopes by combining a surface-deployed geosynthetic with an anchoring system of driven reinforcing rods similar to soil nailing. Installation of the system involves tensioning a geosynthetic over a slope’s surface by driving anchors through the geosynthetic at a given spacing and distance. By tensioning the geosynthetic over the slope’s surface, a compressive load is applied to the slope. Benefits of AGS are described to include the following: ( a) increased soil strength due to soil compression, including increased compressive loading on potential failure surfaces; ( b) soil reinforcement through soil nailing; ( c) halt of soil creep; ( d) erosion control; and ( e) long-term soil consolidation. Following installation of the AGS and 1 year of monitoring, it was found that the anchored geosynthetic system provided only some of the reported benefits and in general did not function as an active stabilization system. This was in part because the system could not provide and maintain loading on the geosynthetic. The geosynthetic, however, did tension when slope movement occurred, preventing the slope from failing. Thus, the system functioned more as a passive restraint system and appeared to function well over the monitoring period.