Analysis on the Basic Characteristics and Formation Mechanism Landslide under Rainfall Conditions and River Erosion

摘要

At 21:30 p.m.of the 16th in July, 2009, the slide has been taken place in the Dafengtan of Gufeng village of Fankuai town of Xuanhan of Sichuan in China.The volume of slide is about 50×104m3, the maximum sliding distance is 40m, and about 10×104m3 sliding body substances run into the river to bloke more than half of the river (about 40m), sliding material diverted river, which cause collapse of public housing and destruction of related facilities, economic loss is large.Based on geology and precipitation, it analysis comprehensively the formation mechanism of the landslide and explains the reasons for the formation of the disaster.The landslide is the result of many factors, but the role of each factor is different.The main factors are storm water, geological conditions of being easy to slide, and irrational human activities.Powerful rain played an erosion, jacking, wedge cracking, motivate role.The course of the landslide includes four steps: namely groundwater convergence-jacking the landslide body, river rise-scouring the foot, squeeze-wedge crack and collapse crack-slide.It has some guidance for prevention disaster work of disaster risks point in Southwest China to further study the formation conditions and the presence mechanism of Gufeng village landslide in Fan Kuai town.