Slope stability analysis using Bishop and Finite Element Methods
Munira Sungkar, M Munirwansyah, Reza Pahlevi Munirwan, Dewi safrina
Abstract
Abstract Analysis of slope stability in this study aims to determine the safety factor (SF) of the landslide for the existing and the reinforcement condition. The study case was in STA 84+910 of national road Meulaboh-Geumpang, West Aceh Regency in Aceh Province. The condition of the Meulaboh-Geumpang road often causes landslides due to the topography of the area and is also triggered by rainfall. The analysis of safety factor for the existing condition was calculated by using the Bishop method that assumes a circular failure surface and the calculation was also validated by the finite element method using 2D Plaxis version 8.6 software. However, computation requires iterative procedures because of the nonlinear relationship for the safety factors. The result obtained from calculations using the Bishop method for the existing condition is 1.08, while by using Plaxis software, the result is 1.10, which means the slopes are in unstable conditions and need to be reinforced to prevent landslides. Alternative reinforcement was conducted by using sheet pile and calculations performed using 2D Plaxis version 8.6 software. Variations in the placement of sheet piles are at the upper and middle of the slope. The results obtained from the calculation of the safety factor after reinforcement are 1.57 (with a 12m sheet pile depth at the upper slope) and 1.48 (with a 10m sheet pile depth in the middle of the slope).