Slope Stability Analysis Using Stress States Obtained from Finite Element Analysis

Abstract

This paper presents the stability analysis results of soil slopes having 2 m high and 3 m wide, using GeoStudio (SLOPE/W) program that employed the strength reduction method based on stress states obtained by finite element analysis. Then, they were compared to the stability analysis results obtained from limit equilibrium method that is commonly being utilised at present day. For sandy clay, the analysis began by defining the cohesion and frictional angle of 30 kPa and in a range of 0 – 40 degree, respectively. In the case of clayey sand, the frictional angle was 30 degree, while the cohesion ranged from 0 to 80 kPa. To compare the results obtained from the two methods, it was achieved by considering the same soil slice that had cohesion and frictional angle of 30 kPa and 30 degree, respectively. Subsequently, a radius for the slip circle to be analysed was arbitrarily defined. For clay-sand mixture slopes, when considering overall results, it was found that a factor of safety obtained from the FEM is higher than those obtained from the LEM, except for the case of the slopes having the frictional angles of 0 and 1 degree. The comparison of results from both methods showed that a factor of safety obtained from the FEM was 2.542, while the LEM yielded the value of 2.462. This indicates that the conventional analysis method provides a result similar to that obtained by the FEM.