Non-local μ(I) rheology improves landslide deposition modeling in MLS-MPM simulations

Abstract

Gaining insights into landslide deposits form can help achieve a better understanding of the overall landslide dynamics. Previous studies have focused on understanding global characteristics of the runout process and final deposit, without attempting to comprehend the deposition process and the underlying mechanisms. Here, we employed a combination of flume experiments and numerical simulations based on the material point method (MPM) to investigate the influence of friction on the characteristics of rock avalanche deposits and gain a deeper understanding of the mechanisms involved. MPM simulations have generally relied on simple soil constitutive models, which cannot capture the rate-, pressure-, and size-dependent characteristics of geomaterials. Thus, we adopted a viscoplastic non-local μ(I) rheology model, which has been proven to be able to reproduce depositional characteristics with high accuracy. We identified two stages during deposition, namely a translational stage, primarily influenced by the basal frictional resistance, and a subsequent impact shear stage, governed by the internal frictional resistance.