Stability Evaluation Of Typical Single Landslides In The Southern Foothills Of Qinling Mountains

The hejiacao landslide is located in the southern slope of Qinling Mountains.It is 303 m long on the northwest slope of the mount RI,with an average width of 50 m,with an average thickness of 15 m and a main slip direction of 307 degrees,in Zhen'an County.In the past 30 years,with the rapid development of the economy in Zhen An county,the construction of infrastructure construction has greatly changed the natural stress distribution of the landslide body,such as high digging and low filling,cutting slope angle and building a wall.In addition,the landslide area is located in the fracture zone,the local rainfall intensity is large and the frequency of the rainstorm is high.Under the influence of these factors,the landslide body appears again in recent years.With the increase of time deformation,it seriously threatens the safety of people's lives,property,transportation facilities,social welfare facilities and schools in the area of the hejiacao landslide.On the basis of sufficient collection of relevant data,this paper discusses the engineering geological characteristics of the landslide,studies the formation conditions of the development characteristics of the landslide,and analyzes the evolution mechanism of the landslide and the characteristics of the deformation and failure.Finally,based on the limit equilibrium method and the finite element analysis of GeoStudio software,the stability of landslide under natural and rainstorm conditions is comprehensively evaluated and analyzed.To get the following understanding:The main landslide is in the state of stability and stability in the natural state.Under the condition of heavy rain,the landslide stability decreases and the landslide is in the state of under stable and unstable,and the landslide will slip deformation.The magnitude of rainfall intensity is closely related to the stability coefficient.The main cause of the landslide is that the infiltration of rainwater leads to the rise of the groundwater level line,which reduces the effective stress on the potential sliding surface,that is,the corresponding shear strength,so that the soil is softened.The stability calculation based on the limit equilibrium method has little difference with the stability coefficient obtained by the numerical simulation based on GeoStudio.It can prove that the selection of the evaluation method and the establishment of the model are both reasonable and correct.