Study On Formation Mechanism And Stability Of Loess Landslide In Beipo Village Of Didian County,Baoji City

Landslide is a serious geological disaster,characterized by destructive and irreversible damage.This disaster poses a great potential threat to the lives and property of people in prone to disaster areas.Many large-scale loess landslides have developed in large numbers in the Loess Plateau of Northwest China.Especially under the influence of atmospheric precipitation and earthquakes,loess landslides occur frequently.Baoji area locates in the western part of Guanzhong Plain.The geological environment is relatively complicated.The geological disasters dominated by landslides and collapses are developed and always restrict the development of the local economy.This paper takes the Beipo Village landslide as the research object at Chencang District in Baoji City of Shaanxi Province.Through the field investigation of the landslide and the analysis of relevant geotechnical test data,the finite element software is used to simulate the landslide under different working conditions.The landslide stability under different working conditions was simulated and the conclusions were drawn.According to the conclusions,corresponding comprehensive measures were proposed for the Beipo Village landslide.The details are as follows:(1)Through the review of relevant data and on-site field surveys,a detailed understanding of this area basic profile is carried out,such as regional geological structures(faults include Weihe fault,northern margin front fault at Qinling and Badu-Guozhen fault),meteorology and hydrology,stratum and lithology(mudstone,pebble layer,loess,loess soil,silty clay),groundwater(pore water of loose rock,confined water).And geotechnical engineering characteristic in the area is got aceording to relevant laboratory tests.(2)The structural and deformation characteristics,and influencing factors of this landslide are described in detail.The intrinsic influencing factors are mainly slope morphology,slope structure,geostress and stratum distribution.The external factors including meteorological conditions,earthquake action,human activities and vegetation destruction.And a detailed analysis of its development process and formation mechanism is performed.(3)In the landslide stability analysis,based on limit equilibrium method,the three working conditions(self-weight working condition,self-weight plus rainfall working condition,and self-weight plus seismic working condition)of five sections is calculated respectively by using the Lizheng software.The stability coefficient Fs and the landslide thrust under various working conditions are obtained.The finite element software ABAQUS is used to simulate the landslide in three working conditions by the reduction factor method.The landslide stability is analyzed deeply and compared with the results obtained by the limit equilibrium method.The calculation results are basically consistent with the limit equilibrium method.The difference in the author'5 view is due to the limitation of the limit equilibrium method in the landslide engineering.The comprehensive result of the landslide stability is that the landslide is in basically a stable state to a steady state under self-weight conditions.In the case of self-weight plus rainfall working condition,and self-weight plus seismic working condition,the working conditions are in unstable state to under steady state.(4)Based on the research results,combined with the area actual situation and the prediction of the landslide development degree,the corresponding comprehensive treatment suggestions for the landslide are proposed.(5)To demonstrate the comprehensive management suggestions put forward in this paper,CEO5 2018-soil slope stability analysis software is used to calculate the stability coefficient of soil slope under various working conditions after treatment with micro-pile,and the design scheme of drainage system is given further.