Effects of backfill on the performance of GRS retaining walls

Abstract

In this study, a finite element program was validated by comparing its analytical results with the results of a well-instrumented large-scale laboratory test conducted on a geosynthetic reinforced soil (GRS) retaining wall under well-controlled test conditions. The validated computer program was then used to investigate the effects of backfill type on the behavior of GRS retaining walls. Three different geosynthetic reinforcements and sixteen different backfills were implemented in the analysis of three different wall configurations to produce 144 analysis combinations. It was shown that the type of backfill had the most profound effect on the behavior of the GRS retaining wall. It was also shown that the stiffness of the geosynthetic reinforcement had a considerable effect on the behavior of the GRS retaining wall when the backfill was of lower stiffness and shear strength. A parametric study was performed on GRS retaining walls based on the finite element analyses to assist the design engineer in choosing the appropriate backfill and the appropriate geosynthetic reinforcement for GRS retaining walls in order to satisfy the prescribed requirements of maximum lateral displacement, maximum axial strain in the reinforcements, and/or average safety factors.