Abstract: Based on the finite element method, a numerical simulation study on slope stability under extreme rainfall conditions was carried out with the focus on the influence of rainfall intensity and duration on the slope stability. The results indicate that the slope factor of safety decreases significantly with the increasing rainfall intensity and the prolonged duration. Under long-duration, high-intensity rainfall conditions, the slope is more prone to approaching a critical failure state. On this basis, the critical slip surface and factor of safety before and after rainfall infiltration are analyzed in combination with the response mechanism of pore water pressure within the slope under rainfall infiltration conditions. The reinforcement effect of a combined support system consisting of prestressed ground anchors and rock bolts is evaluated. The results show that this support scheme improves the stress state of the slope through the action of prestress, causing the critical slip surface to move deeper into the rock-soil mass. The research findings can provide a theoretical basis for optimizing support design of slope engineering under similar geological and meteorological conditions.

Key words: Finite Element Method, Slope Stability, Rainfall Intensity, Slope Engineering, Numerical Simulation