Study On The Participation And Stability Of Large Landslide Sliding Zone Soil Under Complex Geological Conditions

This paper studies the landslide in the Cailou Village of Huangling Town.It is located in the Yunfu-Zhanjiang section of Shantou-Zhanjiang Expressway and the TJ17 mark K162+180-380 section of the A4 contract section of the branch project.Based on the geological hazards control of the landslide,combined with the preliminary site investigation data,the basic characteristics and formation and evolution mechanism of the landslide are analyzed by combining quantitative and qualitative methods.Research the shear strength parameter of the sliding zone soil of the landslide,evaluate the stability of the landslide and put forward the reasonable prevention and control project.The main tasks are as follows:(1)The geological environment of the landslide area was obtained in detail by collecting relevant data and conducting field investigation in the early stage.Analyze the basic characteristics,influencing factors and deformation mechanism of the landslide in detail.According to the core drilling and sampling results of two typical fracture surfaces in the landslide area,as well as the deep displacementt monitoring,the sliding surface position of the landslide is reasonably analyzed.(2)On the basis of in-situ test and laboratory geotechnical test,the shear strength parameter of the sliding zone soil is analyzed deeply and inverted by Flac3 d numerical simulation.Then,compare the shear strength parameters of sliding zone soil in similar areas around,and the shear strength parameter of the sliding zone soil is finally obtained by the combination of the methods of analytic hierarchy process,qualitative analysis and quantitative analysis.(3)The stability of the slope is analyzed by the transfer coefficient method,and it is concluded that the slope is under-stable in natural conditions and unstable in rainstorm conditions.Four different limit equilibrium methods are used to calculate the minimum safety factor of the slope in naturally saturated conditions respectively.The results are basically consistent with the transfer coefficient method.Use Flac3 d to conduct numerical simulation of the slope.Under natural working conditions,the plastic zone issmall,fails to form a penetration,and the danger is relatively small.Under torrential rain conditions,some plastic zones form a penetration,which is more dangerous,and the slope is likely to be unstable.(4)According to the basic characteristics of the landslide in the Cailou village of Huangling Town and the results of stability analysis,a reasonable prevention and control project plan is put forward.