Search For Three-dimensional Critical Slip Surface Of Slopes Based On Minimum Potential Energy Method

At present,by the factor of nature and human-beings,landslide becomes more and more frequently and serious that the casualties and economic losses cannot be estimated.When becomes unstable,the sliding mass will slide along the most dangerous slip surface.Therefore,under certain conditions,finding out the critical slip surface corresponding to the minimum safety factor of the slope has important theoretical and practical significance in the face of predicting and reducing landslide disasters.The slope instability shows a three-dimensional shape.But it has no mature method for search for the three-dimensional critical slip surface so far.The research in the field is still in the exploration and development.This paper,supported by National Natural Science Foundation of China Project(NO.51304084)and based on the former works,has a research of searching for three-dimensional critical slip surface of slopes based on minimum potential energy method.The main work of this paper includes the following parts:(1)Aiming at the slope of ellipsoidal slip surface and establishing a basic mechanical model,the theoretical derivation of the three-dimensional minimum potential energy method for the stability analysis of the slope is carried out.Taking the sliding mass as a rigid body and then establishing the calculation model,the elastic potential energy and the shear potential energy are calculated for obtaining the total potential energy.Through the relationship between force and displacement,calculated from the principle of minimum potential energy,the anti-slide force and the sliding force are solved.Therefore,the slope safety factor is obtained.(2)Based on the minimum potential energy method,the paper carried out the study,genetic algorithm(GA)searches for three-dimensional critical slip surface of slope.Putting forward a method of establishing ellipsoidal slip surface only with 6 parameters,the searching objective function is determined.Then using GA,an intelligent optimization method,realized searching for the critical slip surface.(3)Through classic slope example and model test two ways,the test study of this paper method is carried out.By comparing the search results of this paper method with the results of other methods and actual failure surface,the feasibility of this paper method is verified.(4)Based on MATLAB software,the program of searching for critical slip surface is designed.The theory of this paper method is compiled into a computational program and a search program,then combining the interface program and the package program,the search program is realized.(5)Through the actual slope engineering,the application of this paper method is carried out.According to the search results,the stability of the slope under current state is predicted.It shows that this paper method has good engineering practical value.