Modelling cliff collapse and run-out with the material point method

Abstract

This paper proposes a method for modelling the combined collapse and large deformation run-out of cliffs using the Material Point Method (MPM). An explicit dynamic MPM formulation is derived with features key for simulating ductile–brittle fracture dynamics over varying timescales. An isotropic non-local plastic-damage scheme is presented that may be used to simulate crack initiation and growth leading to brittle collapse of a cliff. The scheme is applicable to both quasi-static and dynamic cases. The behaviour of the proposed plastic-damage model is compared to experimental data utilising numerical shear-box tests. A numerical case study is carried out on a real-world chalk cliff to show the model’s applicability to rock-slope mechanics in both failure initiation and post-failure run-out.