The Study On The Formation Mechanism And Stability Of Jiuli Landslide

Landslide is a multiple geological disasters, which widely distribute in the world and cause serious damage. It not only threats people’s life and property but also destructives to the environment and resources. In recent years, with the rapid development of the world economy and population increase, human beings are developing a large scale of the slope. Coupled with the2008Wenchuan earthquake in Sichuan Province, the geological condition has had the huge change, which caused serious damage to the geological environment. At the same time, the global climate warming and the increase of rainfall increases the deformation and failure of slope scale, which make collapse、landslide、debris flow occurred continuously. Therefore, the prevention of geological disaster situation is very serious. Now, the main research trend of slope deformation is through the study of the mechanism of landslide, according to the sliding mode to improve the theory and method of slope stability analysis and the landslide treatment technology. It gradually achieves the method of the reasonable treatment and control of landslide, scientific evaluation and prediction of landslide stability. It not only achieve the rationality and economy of engineering but also ensure the safety of property.In thesis, it bases on detailed geological investigation, deformation monitoring data and previous research results. It analysis the geological environment characteristics、the phenomenon of deformation、growth characteristics、forming factors and formation mechanism of Jiuli landslide. Starting from the analysis of the geological environment characteristics、deformation phenomena and development characteristics of Jiuli landslide, it analysis formation conditions and formation mechanism of landslide. At the same time, the thesis uses analysis method of limit equilibrium and numerical simulation to study on stability and formation mechanism of Jiuli landslide in detail and predict the development tendency of Jiuli landslide. The thesis achieves the following major research result:(1) Through the analysis of results of local geological investigation, Jiuli landslide is influenced by the Jiusha river incised and rainfall factors which occurred creep deformation. There are two creep deformation planes, the shallow plane is completely holing-through, while the deep plane is not completely holing-through. At present, the landslide is under in the creeping stage, in case of heavy rainfall, the landslide will fast creep, formed holing-through slide plane and occurred fast slide, leading to more large-scale rock mass slide.(2) Through the analysis of results of local geological investigation and monitoring results, which grasp the geological environment characteristics、the phenomenon of deformation、growth characteristics of Jiuli landslide and analysis formation conditions and formation mechanism.(3) Using the analysis method of limit equilibrium and numerical simulation, the results showed that, Jiuli landslide is in the state of limit equilibrium under natural conditions, the shallow sliding mass happen local instability, the deformation is mainly located in the shallow sliding mass; Jiuli landslide is in the state of instability under rain saturated conditions, the shallow sliding mass happen deformation failure, while the deep sliding mass’s deformation gradually accumulate, which occurred trend of damage. Compared the calculation results with local geological analysis, we know that the analysis result is basically the same, which show that the calculation model and parameter is reasonable.(4) Compared the numerical simulation results with monitoring results, we know the analysis results are consistent with the stability analysis, which show that Jiuli landslide formation mechanism consistent with the actual situation.