Simulation of Senise landslide in clayey silty soil using a strain softening soil model and Updated Lagrangian H-Adaptive approach

Abstract

Senise landslide in the southern Italy occurred in July 1986 due to the existence of a thin layer of clayey silt, interbedded with a slightly cemented sand formation. Excavation at the toe of the slope has lead to the occurrence of landslide. This is accompanied by progressive failure, mainly due to the softening behaviour of the thin clayey silt layer. The landslide is simulated using the developed finite element code that combines the Updated Lagrangian formulation and a strain softening model. This code is capable of simulating the development of the progressive failure. Simulation of slope failure in highly strain softening soils results in the distortion of finite element mesh; therefore, a proper numerical discretisation is prepared by an H-Adaptive remeshing technique to ensure that the analysis and leads to reliable results and solution convergence. The results of this study show the location and extent of failure zones. The failure is shown to be triggered by excavation at the toe of the slope and extends upward along the thin clayey silt layer. Compared with the observation, the numerical analysis could simulate the location of failure surface and the sliding soil mass reasonably well.