Rainfall infiltration model of Huangtupo landslide in Three Gorges Reservoir area

The influences of slope angle and rainfall intensity on infiltration process of landslides are not considered in the traditional rainfall infiltration model. In order to describe the rainfall infiltration process of Huangtupo landslide better, an improved infiltration model considering the influence of slope angle and light rainfall intensity is deduced based on the Green-Ampt infiltration model. In order to obtain the parameters of the improved infiltration model, double rings infiltration tests, rainfall monitoring, water content and matric suction monitoring are conducted on the No. 1 slide of Huangtupo landslide. The results show that the saturated hydraulic conductivity of the rock falls of No. 1 slide of Huangtupo landslide is about 4.81x10(-5) m/s; water content increases under continuous rainfall and decreases under the cessation of rainfall, and the effect of hysteresis occurs in the deeper soil; on the contrary, the matric suction decreases under continuous rainfall and increases under the cessation of rainfall. The parameters of the improved infiltration model of Huangtupo landslide are get. The results calculated from the improved infiltration model are very close to the data obtained from monitoring. Therefore, the improved infiltration model can be used to rainfall infiltration analysis on Huangtupo landslide.