Geotechnical Modeling of Municipal Solid Waste Landfill Slope Stability: Two-Dimensional and Three-dimensional Limit Equilibrium Analyses

Abstract

This study conducts a comparative evaluation of 2D and 3D slope stability analyses for landfill applications under varying geometric and hydrogeological conditions. Stability assessments were performed using Slide2 and Slide3 software, applying the limit equilibrium method with the Morgenstern-Price formulation to determine critical failure surfaces and corresponding factors of safety. two hydrogeological scenarios: (1) an unsaturated condition with zero pore-water pressure and (2) a saturated condition with a 17-meters piezometric level. Results indicate that 3D modeling enhances spatial resolution, enabling precise identification of localized instability zones. However, despite its geometric simplifications, the 2D approach remains reliable. These findings suggest that the decision between 2D and 3D analyses should account for factors such as landfill geometry, computational resources, and the required precision for risk assessment.