Parametric Study and Analysis of Slope Stability Using Finite Element Method in the Case Of; Dodola-Edo Sorofta - Werka Road Project

Abstract

Slope stability analysis is a critical aspect of geotechnical engineering, evaluating the stability ofnatural and man-made slopes under various loading conditions. This analysis is particularlyimportant in Ethiopia, where factors such as slope angle, improper land use, surface andgroundwater, and soil type contribute to slope instability, especially during the wet season whenprecipitation is the primary cause of landslides. Understanding these causes is crucial for designingand constructing safe, sustainable infrastructure and repairing slopes that fail prematurely. This casestudy focuses on the Edo to Werka road, specifically the section from station 26+230 to 26+302 onthe right-hand side (RHS), which is at significant risk of slope failures due to its construction onmountainous terrain. Located at 39??03'09.4048"E longitude and 6??50'05.7039"N latitude, this arearequires a thorough geotechnical investigation, including laboratory tests, to gather data for slopestability analysis. Using the Finite Element Method (FEM) to determine the factor of safety (FoS) forthe given slope geometry, it was found that increases in cohesiveness and the angle of internal frictionsignificantly enhance slope stability. Conversely, reducing cohesion decreases the FoS, highlightingthe slope's vulnerability to failure, while increasing the internal angle of friction allows the soil tosustain steeper slopes without failure.