Landslide was caused by liquefaction in submarine sandy or silty slope due to earthquake. Based on effective stress finite element method and Newmark’s sliding block theory

simplified approach was developed for evaluating lateral slide displacements induced by liquefaction due to earthquake on submerged gentle slope (≤5o). Wave loads were simplified as constant pressure and initial excess pore pressure. Viscosity of seawater was ignored during dynamic analysis. Liquefaction analysis was conducted using improved Seed’s pore pressure model. According to Newmark’s model

accumulated lateral displacements of submerged slope were achieved during earthquake. By examples

effects of slope angle and sea depth were studied and the validity of the new analysis was confirmed. The method can be used to predict earthquake-induced submarine geological damages in offshore engineering fields.