Stability analysis of unsupported vertical cuts in the vadose zone using 2D and 3D numerical methods

Abstract

Evidence supporting the implementation of three-dimensional (3D) slope stability analysis in geotechnical engineering practice has been mounting since the nineteen-seventies. Current levels of computational power and its accessibility has allowed researchers to investigate the significance of the 3D numerical analysis output compared to conventional 2D limit equilibrium approach. This study compares results of stability analyses of unsupported vertical cuts in the vadose zone using both 2D (GeoStudio 2019 R2) and 3D (FLAC3D) software. Numerical analyses are carried out for various dimensions of unsupported vertical cuts excavated in an unsaturated glacial till. The findings from two different methods (i.e. 2D and 3D) and the limitations of 2D stability analysis are discussed.