Slope Stability Evaluations Using Limit Equilibrium and Finite Element Methods

Abstract

Landslide occurrences in Malaysia cause huge economic losses each year and have resulted in over 600 recorded casualties from 1961 to 2011. It is therefore overdue for practitioners and researchers alike in Malaysia to re-evaluate slope stability in high-risk areas prior to any mitigation work. In this study, the case study is focused on one such slope stability evaluation that was conducted at a landslide-prone location, i.e., Maktab Rendah Sains MARA (MRSM), Bentong, Pahang. The evaluation uses limit equilibrium and finite element methods; more specifically, SLOPE/W software for the limit equilibrium method and PLAXIS software for the finite element method. The primary distinction between these two analytical approaches is that finite element methods are based on the stress–strain relationship of the soil whereas limit equilibrium methods are based on static equilibrium that divide sliding mass into smaller slices. Here limit equilibrium methods collectively represent a conventional approach in which the fundamental principles of static equilibrium and interslice forces are used in the past. Conversely, finite element approaches serve as a more realistic indicator for the factor of safety in the absence of stress distribution data. The simulations showed that both methods produce results that are not significantly different, but the use of the finite element method proves to be best-suited for complicated geometries, as those experienced in Malaysia.