Discrete element analysis of structural characteristics of stepped reinforced soil retaining wall

Abstract

Based on the laboratory large scale model test of the stepped reinforced soil retaining wall (RSRW), the discrete element numerical model of stepped RSRW is set up by particle flow code. The displacement of particles, stress distribution, force chain distribution, and potential failure surface of the stepped RSRW are analyzed by simulating the loading process. The results show that the geogrid can confine the horizontal displacement of soil and reinforce soil effectively. The geogrid endures the soil pressure of upside and transmits the pressure to surrounding soil, and improves the distribution of vertical soil pressure of the stepped RSRW. The number of strong force chains in the reinforced area is obviously higher than in the unreinforced area, which verifies that the geogrid can strengthen the soil. The soil particles have been in a plastic flow state and formed a continuous sliding surface at the front of retaining wall, but there was no obvious crack in the retaining wall. The potential failure surface of the stepped RSRW can be determined by observing the changes of force chain structure. The numerical simulation result of the potential failure surface is in good agreement with the theoretical calculation.