LAUSR

Abstract The investigation of mechanisms of multiple slope failure and the displacement of the resulting failure mass is highly important for the safety of the mountainous environments of the world. This study attempts to investigate such phenomena through numerical analysis. A one-dimensional (1D) surface flow and erosion/deposition model, a two-dimensional (2D) seepage flow model, a 2D slope stability model (the Spencer method of slope stability analysis), and a 1D sliding block model were combined as a single unit such that the developed model can also successfully analyze the surface water flow and erosion/deposition on the model slope soil surface, seepage-flow phenomena within the soil domain, and stability of the model slope during the movement of the sliding mass by updating the shape of the model slope according to the new position of the sliding mass. The Spencer method of slope stability analysis was incorporated into dynamic programming to predict the time of a slope failure and the shape of the failure surface. The data obtained from the numerical simulation results were compared with the experimental data obtained from Regmi et al. (2014) for validation. The application of the model in the real field would have significant impact for appropriate mitigation measures against probable disasters that may be caused by rainfall-induced landslides and slope failures.