Study on rainfall early warning model for Xiangmi Lake slope based on unsaturated soil mechanics

Urban expansion caused numerous geological hazards, particularly in the mountainous areas. In this article, the unsaturated soil mechanics combined with a numerical method is applied to build the rainfall thresholds for the Xiangmi Lake slope in early warning. The drainage mechanism in soil slope under different rainfall conditions has been studied. Then, the actual rainfall data collected in the rainy season are taken as the rainfall condition to simulate the actual rainfall situation. The corresponding safety factor of the slope under the rainfall has been calculated and compared with the improved deformation tangential angle criterion for the slope safety prediction. The tangent angle can be used as the judgment basis to classify the early warning levels of a rainstorm, which helps to establish the early warning model of slope rainfall and guide the landslide early warning.