Study On Stability Of Landslide And Optimization Design Of Treatment Reinforcement Engineering Based On Monte-Carlo Method

Landslide,as a serious geological hazard,threatens the safety of human life and property.In the past,the safety factor method was used for the evaluation of landslide stability and the design of reinforcement engineering.Although the safety factor method considers the uncertain factors such as accidental loading,this method cannot quantify the potential risk degree of landslide and reinforcement engineering.However,the reliability theory takes into account the uncertainty factors such as the parameter variability of geotechnical parameters and the reliability of the reinforcement engineering of the landslide and it can evaluate the risk degree of landslide and reinforcement engineering.In this paper,taking Ranjiagou 9~thh landslide as an example,we analysis the basic morphological characteristics,influencing factors and genetic mechanism of the landslide are determined according to the engineering geological conditions of the landslide.On this basis,using the method of transfer coefficient as the function of landslide stability coefficient establish performance function,taking and Monte-Carlo method calculate the reliability and failure probability of landslide stability.Finally,we compare the calculation results of Monte-Carlo method and transfer coefficient method and evaluate the stability of landslide.Compared with transfer coefficient method,Monte-Carlo method can not only obtain the landslide stability coefficient of the mean,at the same time be able to get the failure probability of landslide,namely the size of the potential instability of landslide possibility,this is the transfer coefficient method cannot get conclusion,which to avoid the simplification and the calculation results of absolute.Based on the evaluation results of landslide stability,this paper comprehensively considers the thickness of the slip mass and the size of the esidual downslide thrust and adopts the control measures of anti-slide pile reinforcement.Aiming at the design of anti-slide pile,we discuss the reliability design method of anchorage depth.Firstly,derived the calculation formula of the Horizontal allowable bearing capacity of the anchorage section by using the mohr-coulomb strength criterion,and established the limit state function function.We discuss the reliability of anchoring depth under two kinds of variation coefficient,found that the anti-slide pile anchorage depth reliability index of the sensitivity of the parameter variability,along with the rising of the coefficient of variation of parameters,the anchoring depth,under the same reliable indicator will be significantly reduced.In addition,we define achieve the smallest anchoring depth of target reliability index is called the anchoring depth,based on target anchoring depth determine the critical value of anti-slide pile anchorage depth,guide the anti-slide pile design.