Integrated numerical study of rainfall-induced landslides from initiation to propagation using saturation-based rheological model

This paper presents an integrated two-dimensional numerical framework for simulating rainfall-induced landslides from instability initiation to post-failure flow. To describe the entire process, three steps are considered in this study: 1) a coupled hydro-stability analysis which detects the failure plane using the Finite Element Method (FEM) (pre-failure stage), 2) computing the local rheology of the failed mass (wet sandy soil) based on the water saturation at the onset of failure, using the saturation-based rheological model (transition stage), and 3) a continuum-based propagation analysis which solves the flow of the wet material by employing the Smoothed Particle Hydrodynamics (SPH) method (post-failure stage). Finally, to investigate the influence of rheological model on the post-failure behavior, the computed final deposition profile and flow kinetic energy are compared with those of a viscoplastic model.