A new approach for modeling landslide movement over 3D topography using 3D discontinuous deformation analysis

Landslide movement analysis over three-dimensional (3D) topography is crucial for hazard evaluation and prevention. This paper presents a new approach to simulate landslide movement considering the 3D spatial effects of both the landslide mass and topography using discontinuous deformation analysis (DDA). The approach involves two aspects: the ordered blocky topography (OBT) treatment for the base slope and an algorithm for fast contact detection between the landslide block (LB) and the OBT. By introducing the OBT treatment, the LB-OBT contact detection can be simplified from the global range to the local sub-topography using the current algorithm, which enhances the computation efficiency. The approach has been implemented in the 3D-DDA program. Finally, the capability and performance of the proposed approach for landslide movement modeling were well demonstrated by two numerical examples.