Influence of foundation soil conditions on the service performance of GRS abutments

This paper presents a numerical investigation of the influence of foundation soil conditions on the performance of geosynthetic reinforced soil (GRS) abutments under service load conditions. The backfill soil was considered as a dense sand, and the foundation soils were simulated with four different granular soils representing different density states ranging from loose to very dense sand. The backfill soil and foundation soils were simulated using a nonlinear elastoplastic constitutive model. Results indicate that as foundation soil density decreases, facing displacements and bridge seat settlements increase, and the effect becomes more pronounced for higher vertical stress. The maximum tensile forces in the bottom layer are much larger when constructed on loose foundation soil due to the lower stiffness and strength. A parametric study was conducted to evaluate the influence of reinforced soil foundation (RSF) on the performance of GRS abutments constructed on loose granular foundations. The implementation of RSF could effectively reduce abutment deformations and reinforcement tensile forces, and the GRS abutment would show good performance similar to that constructed on a competent foundation.