Discussion on Slope Stability Coefficient by Limit Equilibrium Method and Finite Element Method

SiJie LIU1

1School of River & Ocean Engineering, Chongqing Jiaotong University, Chongqing, 400074, China

Email:egx136788@163.com

Abstract: Rigid body limit equilibrium method and numerical limit analysis method are commonly used to solve the slope stability coefficient. In order to compare the accuracy of stability coefficients obtained by different methods, the Fellenius method, the simplified Bishop method, the Mongenstern-price method, the strength reduction method and the gravitational loading method were used to compare the results of the typical homogeneous soil slopes and layered soils Slope, and using Mongenstern-price method as the accurate result, statistical analysis of the variation law of stability coefficient error under different methods. The results show that under the assumption that the slip surface is a circular arc surface, the error between the calculated results of the rigid body limit equilibrium method is less than 10%. The simplified Bishop method is highly consistent with the Mongenstern-price method and the result of the Fellenius method The relative error between the strength reduction method and the Mongenstern-price method is between 3% and 12% at different slope angles, and the relative error between the strength reduction method and the Mongenstern-price method is between 3% and 12% %, But the strength reduction method does not need to assume the sliding surface position, can provide all the information of stress, strain, displacement and plastic zone force and deformation, is recommended for the calculation of complex slope stability; gravitational loading ratio method 45 ° complete failure, the slope angle between 45 ° to 60 ° and Mongenstern-price method and strength reduction method has a greater error, only in the slope angle is equal to 75 ° when the results basically meet the requirements, is not recommended.

Keywords: Slope engineering; Limit equilibrium method; Strength reduction method; Gravity ｌｏａｄ method; Stability-coefficient