Terence Ma, Sina Javankhoshdel, Brigid Cami, Reginald E. Hammah, Brent Corkum
The use of software for 3D slope stability is becoming increasingly popular due to advances in computing technology. Though slip surfaces in slope stability are rarely circular in nature, many modern practitioners still rely on limit equilibrium results using spherical or ellipsoidal slip surfaces. Restricting slip surfaces to the spherical or ellipsoidal domain can lead to un-conservative results due to inflexibility of the slip surface during optimization. As the technology for identifying critical slips in slopes continues to improve, a new method which optimizes the shape of a slip surface using flexible splines in 3D was recently proposed. The method is applied in this paper towards the analysis of an open pit mine. Some simplification steps for complex models are presented which are recommended to be taken during the modelling procedure to increase the speed of searching for the critical slip surface and filter out unnecessary entities in the analysis, such as near-vertical weak layers and weak layers with reverse curvature.