A New Continuum Based Model for the Simulation of a Seismically Induced Large-scale Rockslide

Abstract

A powerful earthquake can actuate large number of landslides due to the impact from seismic vibrations. Understanding the mechanism of such seismically induced landslide failures and the resulting landmass runout is crucial for the design of suitable preventive measures. In nature rock slopes occur in a complex physical form, therefore, numerical models are prepared to rationally reflect upon their characteristics. In present study, a numerical analysis has been performed to simulate the post-failure behaviour of a rock slope which is subjected to multi-direction seismic forces for which a continuum model has been adopted. Dynamic Finite Element method available in ABAQUS was used as the computational solver. Since rockslide is a large deformation problem, traditional Lagrangian finite element formulation is incapable of correctly simulating such phenomenon. To address this problem, the Coupled Eulerian Lagrangian (CEL) method has been used in present study. Lagrangian description is given to the stable base block, while Eulerian description is given to the fluid like sliding mass. The seismic motion is applied as a transient boundary condition on the base block. Results showed that seismicity has a major influence on failure of the rock slope. Furthermore, post-failure behaviour of the rock slope reproduced by the CEL based continuum model is fairly in agreement when compared with the results procured from conventional discontinuum modelling approach.