Hydro-mechanical simulations of unsaturated soil slope

Abstract

Rainfall-induced landslides, which are frequent in various parts of the world, cause a substantial loss in infrastructure and are always a risk to public safety. The assessment of such landslides is critical, and therefore, the effect of rainfall on unsaturated soil slope is modeled, and the results of numerical simulations are presented in this paper. Coupled hydro-mechanical simulations are performed using the elastoplastic Barcelona Basic Model (BBM), and the results are presented in terms of the displacement values, the evolution of pore water pressure (PWP), and saturation zones. The obtained results are compared with those of the traditionally used model, i.e., Mohr–Coulomb. As BBM considers the effect of confining pressure and suction, which the Mohr–Coulomb Model does not consider, a considerable difference in the displacement values is found. Moreover, initial failure gets developed upslope as the tensile volumetric plastic strains are concentrated at the top of the slope, suggesting that soil slope does not have to be entirely saturated to experience failure.