Simulation Study On The Failure Of The Guantan Landslide Under The Action Of Earthquake And Rainfall

In May 12, 2008 Wenchuan earthquake occurred geological disasters triggered numerous cans Beach landslide is earthquake-induced landslide secondary disasters in Sichuan Mianyang City Town Jushui river, did not produce the slope under earthquake action landslide, but under the influence of heavy rainfall after the earthquake, in the evening 22:00- 23:00 during slope failure to damage, causing casualties and property losses, and therefore has a very important failure mechanism of its meaning.Mechanism of landslide damage can be divided into model tests and numerical simulation studies. Wherein the model tests mainly through reasonable proportion of the landslide narrow simulation, this method to obtain the relevant parameters by entities experiment, with high credibility. However, this method is usually time-consuming, high-precision test, financial and material resources consumption and other characteristics. Numerical simulation study is to analyze the theory and methods based on computer technology. Through a certain finite element numerical simulation software, programming or a discrete element method for simulation of the actual project situation, the establishment of numerical model. Model by practical engineering analysis of the situation, and then get the numerical values of physical and mechanical parameters of the model and boundary conditions and the like. Obtained by numerical simulation results to analyze the mechanism works destruction.In recent years, methods of particle flow simulation software model has become one of the main methods of geological disasters damage the mechanism of qualitative research. The second chapter of the basic principles of particle flow were introduced, and describes the steps to solve the particle flow of the program, the third chapter introduces the engineering geological conditions of the study area and the basic characteristics of the tank for landslide, Chapter IV software to establish the use of PFC rock uniaxial, biaxial test and attached to particles of different microscopic parameters for solving the corresponding macroscopic parameters to take advantage of this relationship after microscopic parameters on microscopic parameters of the model is calibrated so that the particles can provide a more realistic simulation model of the destruction process, according to the general rules of PFC model simulation model to establish a landslide, added two joints, which are located in the landslide damaged edge pull crack formation region and boundary region. The fifth chapter describes the seismic waves from the acceleration into force, by giving located on the boundary particles exert seismic force to the seismic waves passing to the entire model them; observe the destruction process under earthquake landslides, including the particle velocity, displacement, the overall distribution slope of the horizontal stress changes the vertical stress and shear stress. Chapter VI introduced GEO-Studio software SEEP module calculates water seepage under rainfall slope model to divide the grid to extract seepage force which is added to the PFC model iterative calculation until completely through the sliding surface, landslides destroyed. In this paper, cans beach landslides in the quake- the destruction process under the rainfall of qualitative research. conclusion as below:(1) tank for landslide damage in the earthquake mainly by the lower shale large deformation and slope table and Development joints caused;(2) under the earthquake slope failure process is as follows: First, mudstone largely deformed under the action of seismic forces in the top of the hill a greater tensile cracks, then since the connection between the joint plane is weak, cracks began to develop; with the ongoing earthquake, has in the lower and upper joint surface produces two pull crack and deepening open, the upper part of the slope and surface cracks in communication;(3) under the earthquake displacement gradually increases from the top of the hill and the displacement of the foot of the slope; it is also due to the displacement of the different results in the formation of cracks pull;(4) hydraulic action role model after the earthquake on increasing with the increase of time. After the earthquake slope sliding surface is not completely through, so the landslide damage did not occur; join rainfall numerical simulation results show that the landslide completely through the plastic zone, landslide damage.