Numerical simulation of dynamic catastrophe of slope instability in three Gorges reservoir area based on FEM and SPH method

Affected by continuous heavy rainfall, a large number of landslide disasters occur every year in the Three Gorges Reservoir area, which causes serious property loss and casualties. In this study, we take a typical reservoir slope as an example. Firstly, the change of plastic zone of the slope under the action of continuous heavy rainfall before the failure is simulated based on the FEM method, considering the coupling of seepage field and stress field. Then, based on the smooth particle hydrodynamics method, HBP rheological model and Drucker–Prager yield criterion are used to simulate the dynamic catastrophic process of slope sliding after instability, and the time–space distribution of velocity field and accumulation form of the landslide are obtained based on the N-S equation. By analyzing the erosion behavior at the junction of various materials on the slope, the dynamic mechanism of the slope instability and slippage is revealed.