Geogrid strain and failure surface of two-stage reinforced soil retaining wall under horizontal seismic loading

Based on the large-scale shaking table model tests, the geogrid strain and failure surface of two-stage reinforced soil-retaining wall under horizontal seismic loading are studied. The experimental model is made of backfill, retaining wall and geosynthetics, where the backfill is standard soil, the retaining wall is concrete blocks and the geosynthetics is geogrid. The model height is 1.8 m. The input seismic waves are Wolong waves and EL-Centro waves. The test results show that with the increase of the peak acceleration, the strain value increases, and the maximum strain point extends to the soil interior. With the increase of the peak acceleration, the potential rupture surface gradually extends to the soil interior. Based on the existing methods for calculating the fracture surface, a double-broken line model considering the width of the offset is proposed. The proposed model can be used as a reference for the design of the two-stage reinforced soil retaining wall.