Numerical modeling of clay-rich submarine landslides using a novel material point method coupled with computational fluid dynamics

Abstract Submarine landslides present significant hazards to offshore and nearshore environments. This study presents a novel approach to numerically simulate clay-rich submarine landslide events using a recently developed coupled material point method and computational fluid dynamics (MPM-CFD). The landslide events are modeled from their initiation to deposition. In this method, the soils and bedrock are represented by material point method (MPM), while water and air are modeled by computational fluid dynamics (CFD). The constitutive soil model accounts for both strain softening and strain rate dependency. The method can investigate the interaction with the ambient water, the transition from intact to remolded soils, seabed entrainment, and retrogressive and progressive release mechanisms. This study demonstrated that the MPM-CFD method can successfully replicate submarine slides in both model test experiments and a well-characterized field event. In both cases, the soil parameters are determined from detailed site-specific field and laboratory tests. The numerical simulations successfully replicated the results under both conditions. Consequently, the capability of the model to make class-A predictions makes it as a highly promising framework for predicting future submarine landslide events.