Study On The Influence Of Rainfall On The Stability Of A Soil Slope

In recent decades,the problem of rainfall-induced slope instability has attracted the attention of geotechnical researchers as unsaturated soil mechanics develop rapidly,and the analysis of the effect of rainfall on slope stability becomes an important research topic in geotechnical engineering.As the environmental changes become increasingly complex,external factors that cannot be accurately predicted often lead to the occurrence of slope instability events,furthermore,landslides and debris flows caused by torrential rain have an immeasurable impact on people's life safety and property loss among these slope instability events.This paper is based on the rainfall landslide engineering of a slope stacking by silty clay in Anshan City.Firstly,the geotechnical test is carried out according to the geological exploration and meteorological and hydrological data of the slope,and the change rules of the cohesive force c and the internal friction angle ? of the soil are obtained by analysis,which provides the basis for the numerical simulation analysis in the following paper.Then the hydraulic permeability curve and water-soil characteristic curve of the soil are established based on the soil seepage mechanism of the Green-Ampt model.Based on seepage mechanism and hydraulic-soil curve of soil and the Morgenstern-Price method in the slice method of limit equilibrium,the SEEP/W and SLOPE/W modules in the Geo-studio software are used to analyze the changes of seepage flow and slope stability under rainfall.The results of calculation and analysis show that The greater the rainfall intensity,the greater the slope,the faster the volumetric water content and pore pressure of the slope soil increase,the greater the decrease in matrix suction,and the smaller the safety factor under the combined action of rain intensity,rainfall duration and slope gradient.Finally,in order to analyze the change process of the plastic zone,stress and displacement,based on the strength reduction method,the displacement mutation of the reference point is combined with the plastic penetration zone to be selected as the criterion of whether the slope is instable and damaged or not,and to model seepage and stability of the slope under rainfall by using ABAQUS software.The soil stress decreases sharply,the area of the plastic zone increases rapidly,and the displacement of the slope increases,resulting in a rapid decrease in the safety factor under the combined action of rain intensity,rainfall duration and slope gradient can be revealed.