Stability Of Bedding Rock Slope And Sensitivity Analysis Of Influencing Factors

There are a large number of bedding rock slopes in the red bed area of southwest China.It is inevitable to excavate the toe of this type of slope in engineering construction.Different factors have different effects on its stability.In determining the stability evaluation parameters,the sensitive parameters can be used as the object of the key input,in order to achieve the project objectives while saving the cost of the project.Therefore,it is necessary to study the sensitivity of various factors affecting slope stability.Based on the bedding rock landslide at the left entrance of Shiliangzi tunnel,this paper conducts a sensitivity analysis of the factors affecting the stability of the bedding landslide.The main research contents and conclusions are as follows:(1)The analysis of meteorological and hydrology,topography,stratum lithology,hydrogeology,geological structure and other data in the study area shows that the rock mass in the area is strongly damaged by structure,which provides a material basis for slope instability and damage.Concentrated rainfall makes the rock and soil strength is further weakened.(2)Through the analysis of the temporal and spatial characteristics of the on-site crack development and the mechanical classification,it is concluded that atmospheric rainfall and tunnel construction are the main external causes of landslides.The failure mode of landslides is a composite type of slip cracking and slip bending.And calculated the stability of the landslide under different conditions.(3)With the aid of Rhino software,a simplified 3DEC true three-dimensional landslide numerical simulation model was established,and it was compared with the results of the landslide stability check calculation and the on-site deformation statistics.The results show that the simplified calculation model is basically consistent with the engineering example,and can be used as a benchmark model for sensitivity analysis.(4)Using the 3DEC numerical model that has been verified to conform to the engineering example,the sensitivity analysis of the factors affecting the stability of the landslide was carried out using the single-factor analysis method and the multi-factor analysis method(orthogonal experimental design).The conclusions reached by the two methods are the same.The sensitivity of the stability factors in descending order is: friction angle in rock,friction angle of weak sliding surface,rock cohesion,rock mass,and cohesive force of weak sliding surface.control sliding surface friction angle,control sliding surface cohesion.