Effects Of Rainfall Infiltration On Soil Slope Stability

The rain infiltration is the most important one that results in landslide for unsaturated soil slope. Many landslide investigation shows that landslide is closely related to rainfall. It is of great significance for the precaution of landslide to make a deep study of the landslide law under rainfall and establish a quantitative model for analysis. The variation pore pressure distribution and saturation in unsaturated slope and the slope stability due to rain infiltration is studied in this paper.In this paper, the main works are as follows:Firstly, this paper introduces the saturated-unsaturated seepage theory, and deduces saturated-unsaturated seepage differential equation on the basis of the saturated-unsaturated seepage theory, and explains several kinds of the soil water characteristic curve models, unsaturated coefficients of permeability. On the basis of the theory on water movement in unsaturated soils and water potential in soils, it deduces the theoretical formula of maximum infiltration under rainfall, then lists boundary and initial conditions for the matrix equations of saturated-unsaturated seepage with the rainfall infiltration theory.Then, this paper systematically analysis the influence of pore pressure in unsaturated soils with the variation of rainfall intensity, rainfall duration, rainfall type and coefficient of saturated permeability on the basis of the numerical simulation by ABAQUS software. With unsaturated seepage fluid-solid coupling theory for soil slope, this paper analysis fluid-solid coupling process in rainfall infiltration by numerical simulation.Finally, with the analysis of unsaturated seepage fields, the stability of soil slope is calculated, by means of Shear Strength Reduction Factor methods, the variation of soils slope stability is obtained after rainfall infiltration. Through the analysis of comparative numerical simulation with the project example, we can conclude that the results of numerical simulation of slope stability in this article are realistic, it is can provide a basis for unsaturated soil slope stability analysis, landslide prediction and soil governance, and the results have some theoretical and practical value.