Comparison of Limit Equilibrium and Finite Element Method for Slope Stability Analysis

Slope stability is a critical and extensively researched topic that is important in structural design, especially when slopes are located near residential or civil engineering structures, as human lives are at risk. This paper presents a detailed analysis and evaluation of slope stability, synthesizing current understanding of slope behaviour, soil shear strength parameters, and the methodologies applied in stability assessment. In the conducted parametric study, the stability of slopes composed of fine-grained soils was investigated using both the limit equilibrium method (LEM) and the finite element method (FEM). The principal objective of the research was to assess the influence of soil shear strength parameters on the resulting factor of safety (FoS), while also accounting for variations in slope height. The results of the study show that an increase in soil shear strength parameters leads to a linear increase in FoS, with this relationship being more pronounced for changes in soil cohesion than for changes in the angle of internal friction. The effect of shear strength variations on stability is more pronounced in slopes of smaller height. Furthermore, the comparative analysis indicates that LEM provides more conservative estimates of slope stability in comparison with FEM.