Study On Motion And River-blocking Of Temi Large-Scale Landslide In The Upper Jinsha River

The upper reaches of Jinsha River is rich in water resources,and it is an ideal place for hydropower stations.At the same time,the development of large river blocking landslide is very dense due to the special geological conditions in this area.This paper takes large-scale river blocking landslide as an example.On the basis of summarizing the research results and problems of formation mechanism,movement characteristics and characteristics of river blocking.Start with geological background and engineering geological conditions of Temi landslide,based on data collection and field geological survey,combined with the results of drilling exploration and rock soil test,analysis the development characteristics of Temi landslide and rock soil physical and mechanical properties.Analysis the condition of Temi landslide,study the formation mechanism of landslide and space debris accumulation process.Finally,by collecting 40 cases of large area of the upper reaches of the Jinsha River,The Temi landslide blocking river characteristics and river blocking mechanism is analyzed.(1)According to the landslide area where the geological environmental conditions,combined with the development of the basic characteristics of the landslide,the space that the formation mechanism of landslide can be divided into three stages.First of all,the depression of the valley,the rock mass unloading rebound;secondly,the central rock mass slide toppling deformation;finally the root of rock broken,the sliding surface through.When the shear force is greater than the rock in front of rock shear strength,slope along the high-speed through plane slide,landslide deformation failure models of the space can be summarized as slip toppling-sliding tension type.(2)Through the analysis of the motion characteristics of Temi landslide phenomenon that Temi landslide,consider that space landslide for high-speed remote landslide.The causes of high speed sliding are mainly due to the locking of the leading edge of the landslide,the repeated action of the earthquake in the landslide area and the low resistivity effect during the movement.According to its movement characteristics,the whole process is divided into incubation stage,moving start stage,high-speed flight stage and collision accumulation stage(3)The analysis of the damming characteristics of the landslide shows that Temi landslide has characteristics of large scale and river blocking time is long.On the basis of previous research,analysis of space landslide geological conditions,river bed condition,hydrodynamic conditions,the Temi landslide blocking river mechanism is summarized unloading rebound of incised rock mass in valley?sliding toppling deformation of bedding slope?high-speed sliding?frontal collision accumulation?the trailing edge pushes to form a certain height?ompletely blocking the river.