Seismic rotating stability analysis of retaining wall backfilled by cohesiveless soils considering influence of front cover soils

The seismic rotating stability analysis of gravity retaining walls is always the hot research spot in geotechnical engineering. The retaining wall, backfilled soils behind it and front cover soils are taken as a whole system. According to the upper bound method, assuming that the backfilled soils obey the Mohr-Coulomb criterion, the seismic rotating stability of gravity retaining walls is studied. Considering the effect of front cover soils for a pure rotational failure mechanism assumed, formulas are derived to calculate directly the yield acceleration and the inclination of the failure surface. The optimal solution of the yield acceleration is found. The calculated results are in agreement with the ones obtained by the Mononobe-Okabe method, and the proposed method is validated. The seismic yield acceleration coefficient k_cr increases with the increasing height ratio of front cover soils to backfills (H₂ /H₁). Especially, when the value of H₂ /H₁ is greater than 0.15, k_cr increases rapidly with an increase in H₂ /H₁. Therefore felicitous increase of front cover soils can improve the seismic rotating stability of retaining walls.