Prediction Study Of Movement Characteristics And Impact Intensity Of Accumulation Landslide Of Southern Shaanxi

The mountain area of southern Shaanxi has a special climate,complex structure and fragile geological environment,and a large number of shallow accumulation landslides are distributed,which seriously affect the safety of residents' lives and properties.the prediction of impact disaster intensity of accumulation landslides has important theoretical and practical significance for quantitative assessment of landslide risk.In this paper,on the basis of field investigation and landslide exploration data analysis,combined with indoor geotechnical tests,a three-dimensional numerical model of Fenghuang street landslide is constructed by using particle dispersion method,and the whole process of landslide instability failure,movement accumulation and impact is simulated in advance.the dynamic indexes such as velocity,displacement,energy conversion and impact force of landslide body in the process of landslide movement are studied quantitatively.According to the impact force,the building model at the foot of the landslide is constructed by using the particle flow software(PFC3D)and the finite element software(Midas/gen)respectively,the displacement and stress distribution characteristics of the disaster-bearing body after the impact of the landslide are analyzed,and then the disaster-causing intensity of the landslide is predicted.The results show that the deformation and failure of the trailing edge of the landslide occurs first,and the soil in front is pushed gradually under the action of dead weight,and when the clavicle section of the leading edge passes through,the landslide slides as a whole,which belongs to a typical push landslide.The main sliding time of the landslide is about 30s,the maximum average velocity is 3.25m/s,the maximum displacement is about 38m,and the gravity potential energy is mainly dissipated in the form of friction and collision in the process of movement;after the brick building at the foot of the landslide is impacted by the landslide,the displacement and stress propagate backward and upward,the impact surface of the brick building is destroyed,and obvious collapse and collapse occur.The relevant research methods and results of this paper can provide some reference for the risk assessment of the same type of landslides,especially for the quantitative assessment of vulnerability of disaster-bearing bodies.