Analysis Of Slope Stability Under Complex Rainfall Condition

Rainfall and landslides are two kinds of common natural phenomena in humanlife, rainfall is the main reason induced landslides, both are closely linked.Theanalysis and calculation of saturated-unsaturated seepage field slopeon the infiltrationconditions of the this paper is based on unsaturated soil mechanics theory and thetheory of rainfall infiltration, and on this basis, the slope stability under rainfallconditions were studied and analyzed, which obtained the classification standard for aparticular slope safety grade.The main contents of this study are as follows:(1)Saturated-unsaturated seepage calculation method research; First, the paperintroduces the basic theory of saturated-unsaturated seepage, according to the law ofenergy conservation and Darcy are derived for saturated unsaturated seepage controlequation, and Illustrates the soil water characteristic curve for the solvation thesaturated-unsaturated control differential equation needed; Combination of rainfallinfiltration derived the definite condition for saturated-unsaturated seepage controlequation.(2)Analysis on characteristics of transient seepage field of slope under rainfallinfiltration; Numerical simulation is carried out by using the finite element softwareABAQUS, and makes the systematic analysis of the impact of various factors ofrainfall on the slope under rainfall infiltration cases of transient flow field, includingvariation of pore water pressure, volumetric water content, transient saturated zone, inparticular, the changes with time and space of the pore water pressure and volumetricwater content were summed up and concluded.(3)Slope stability analysis under rainfall infiltration effect; According to theanalysis results of transient seepage field of slope under rainfall infiltration and theshear strength theory of unsaturated soil, and analyzes the stability of the slope, drawsvariation slope stability factor of safety under the appropriate circumstances;Quantitative gives the influence degree of various rainfall factors on slope stability,and makes a comprehensive evaluation of the stability of the slope.(4)How to judge the slope safety is based on the amount of rainfall; Determiningthe critical rainfall of slope landslide occurred; The comparative analysis of actualrainfall and the critical can visually determine the slope of the security situation, bringconvenience for the prevention of landslides. In this paper, a comprehensive analysis of slope in different rainfall intensity,rainfall duration, rainfall patterns,variation of the slope seepage field under rainfallseepage field factors such as soil saturated hydraulic conductivity, and the impact ofchanges in seepage field on slope stability, which gets the method of determiningcritical rainfall of a slope landslide, provides the basis for landslide forecast andgovernance, and has important theoretical significance and practical value.