Elasto-plastic finite element analysis of geogrid-reinforced sandy soil retaining walls considering effect of creep and earthquake

Geosynthetic-reinforced soil retaining walls(GRSRWs) exhibit excellent earthquake-resistant performance during strong earthquakes.However,due to the fact that geosynthetic reinforcements might experience large creep deformation under sustainable loading,it is necessary to investigate the seismic behavior of GRSRWs after long-term creep,as well as the creep behavior after earthquake loading.Elasto-plastic finite element analysis was conducted to analyze the behavior of GRSRWs.The unified constitutive model proposed by the author to describe the creep,stress relaxation and cyclic properties of geosynthetics was used to simulate the reinforcement;a time-independent generalized plasticity model capable of simulating the nonlinear cyclic behavior of sands was used to model the backfill and foundation soils due to the fact that sandy backfill exhibited small creep deformation.It was found that with regular reinforcements,creep deformation would stabilized after sufficient period of time but the internal forces in the reinforcements would be redistributed;the lateral deformation of the wall increased significantly under earthquake loading and the reinforcement forces also increased greatly;after earthquake,the wall experienced considerable creep deformation,while the forces in the reinforcements reduced,but were still larger than those before the earthquake loading.