Evaluation of the Material Point Method in Modeling the Post-failure and Run-Out of Translational Landslide: A Case Study in Taiwan

Abstract

The material point method (MPM) is an extended finite element method used to simulate large deformation scenarios. A massive translational landslide in Taiwan was adopted to validate the numerical technique for thorough investigations, including the digital terrain models (DTMs), laboratory experiments, and numerical analyses were available in a forensic report. The MPM code Anura3D was used to mimic the landslide’s kinematics, post-failure, and run-out process. An unstable sandstone/shale interlayer was found to lead to the slope sliding; therefore, the before-and-after DTMs from the report mentioned above were used to examine the run-out distance and deposition to determine the best fit for reduced material properties for this layer. The sliding paths, displacements, deviatoric strains, and the velocities of the sliding can be evaluated by dividing the material points into several groups to differentiate the kinematics among them. Meanwhile, the landslide duration and possible maximum safety distance were also assessed. This study has demonstrated that the MPM can analyze the large deformation, post-failure, and run-out distance of landslides. The critical timing of a slope failure is possible to be an essential index on national spatial planning for future disaster reduction.