Traction-based SEM-MPM Framework for Multiscale Coseismic Landslide Analysis

Abstract: This paper introduces a new, traction-based framework combining spectral element method (SEM) and material point method (MPM) for multiscale analysis of coseismic landslides. On a regional scale, SEM is employed to simulate seismic wave propagation, accounting for complex geological and topographical conditions. On the local scale, MPM is utilized to model the landslide failure process, capturing failure mechanisms and large deformations. SEM simulation generates traction forces at the local boundaries, which are prescribed to the MPM domain as seismic input. The traction forces coupling effectively addresses multi-scale seismic wave propagation challenges across different computational domains. The method is verified through simulations of point-source wave propagation. Using the actual geological and topographical conditions, the study analyses the characteristics and mechanisms of coseismic landslides at Po Shan Road. The results demonstrate that the proposed method can significantly reduce computational workload while maintaining accuracy, making it a suitable tool for rapid coseismic landslide analysis and hazard assessment.

Acknowledgement: The authors thank the support from State Key Laboratory of Climate Resilience for Coastal Cities at HKUST (ITC-SKLCRCC26EGP1), Hong Kong Research Grants Council General Research Fund 16219424 and Theme-based Research T22-606/23-R.