Study On Sliding Mode And Formation Mechanism Of Loess Landslide In WuQi

In recent years,with the rapid development of local economics and the increasing human engineering activities,the various geological hazard causes the enomous economic losses which takes place frequently in northern ShanXi.The geological hazard was one of the most important factors which impose a great barrier to the development of the economics and the society and worsen the environment. Loess landslide is most abundant in the local geologic hazards, and it is also one of the most disasters which can cause the highest degree of destruction,so it become more and more important to strengthen the study of the sliding modes and formation mechanism about loess landslide.This paper combines with the detailed investigation task of geological disaster in Yan'an of Shan'Xi Province which issued by China Geological Survey Bureau in 2008.On the basis of the laboratory test and the detailed survey of the geological disaster in WuQi,it carried out research work on geology engineering about loess landslide.First of all,this paper has an in-depth analysis to the characteristics of loess landslide and internal and external formation factor of landslide so that rainfall and human engineering activities were the main predisposing factor of loess landslide in WuQi. According to the Structure of gliding mass and characteristics of sliding surface,it Summed up the three sliding modes of loess landslide in this area,such as sliding Along the arc surface,sliding along the linear surface and along the sliding surface of polygonal-shape;It analyses qualitatively the formation mechanism of the landslide by use of soil mechanics, soil dynamics, principle of elastic-plastic mechanics,such as analysis of stress field of landslide,formation process and deformation and failure mode of landslide, focus on an analysis of rain-induced landslide and the project-type landslide formation mechanism. Finally,this paper uses the software of FLAC^2D for a particular slope, simulates the three states ,such as natural state, water effect state and functions of increasing slope angle+the upper loading, from the cloud picture of distribution of maximum shear stress rate, displacement deformation picture and stress distribution picture,it analyses the change and development tendency of landslope and the yield position of shear stress and tensile stress,and has further verification influencing factors of slope failure in loess regions and deformation mechanism of landslide.