Simulating the process of reservoir-impoundment-induced landslide using the extended DDA method

In this work, three extensions to the traditional discontinuous deformation analysis (DDA) method are tested to simulate the entire process describing the behavior of landslides induced by reservoir impoundment. These extensions include the discretization of the area of interest, block gluing and the HM (hydro-mechanical) coupling approach. Several hydraulic boundary conditions are introduced based on the water level during the dry and rainfall seasons. As verification, the entire processes for two practical landslides, the Qianjiangping and the Majiagou landslides, which occurred in the Three Gorges Reservoir (TGR) of China, are simulated. The simulation results agree well with the observed failure modes, indicating that the proposed methodology can intuitively reproduce the entire reservoir impoundment induced landslide process.