Formation Mechanism And Stability Analysis Of Houshan Landslide In Qiaojia County

The landslide is located in qiaojia County,and it is tentatively designated as the houshan landslide in qiaojia County.The overall terrain of the Mountain in qiaojia County is high in the east and low in the west.The terrain is steep and sloping.It presents an obvious landslide topography-circle-chair-like terrain consisting of a steep back wall,side walls and the underlying slope.After the completion of baihetan Reservoir,the water level after normal impoundment is between 765 and 825 meters above sea level,and the county seat and its surrounding areas will be submerged.Although the water level has not yet submerged the landslide front,due to the unique location of the landslide and the construction of the resettlement area,therefore,it is necessary to conduct a systematic and comprehensive assessment of the qiaojia landslide.Based on the results of previous studies,the landslide geology investigation and the auxiliary drilling experiment were used to identify the basic characteristics of the landslide.Based on this,the landslide geological model was established,using numerical software to simulate the Sliding deformation mechanism.Finally,using the limit equilibrium method to calculate the safety factor of the landslide in bad conditions,comprehensively evaluate the stability of the landslide.The main research contents and achievements of this article are as follows:(1)Through collecting geological background data of the study area and reading relevant documents,we understand the key research contents and basic conditions of the landslide,adopt site survey methods to identify the landslide boundary area and surface features which is exposed,and adopt additional drilling methods to identify the lithologic characteristics and hydrogeological characteristics of the landslides.Through rock and soil experiments,the physical and mechanical parameters of the landslide were obtained.(2)Through the survey data and the original data,the original geological profile of the landslide was restored,and the formation mechanism was analyzed by FLAC numerical software.The landslide mechanism main reason is: under the joint action of surface water and earthquakes,the water infiltrates along the fractures in the earth-rock mixture and the fragmented limestone to reach the relative water-repelling layer,gradually formed a argillation interlayer under the creep conditions of the slope.and the shear resistance of the layer was greatly reduced.Tensile cracks were gradually formed at the overload of the rocks,and the shear failure surface developed into a continuous state.The slope slides along the surface.(3)The houshan landslide in qiaojia county is currently in a stable state and its overall resurrection is less likely.According to the site investigation results,there are no obvious signs of landslide surface deformation,and no cracks or dumping have been found in trees,houses,cement pavement etc,only discovered cracks in white locally,surface slope has a small collapse,slippery phenomenon,the formation of debris flow is unlikely,although not rule out the possibility of partial collapse,but the impact on the lives and property of residents is less.