Review of Analytical Methods and Recent Advancement in Slope Stability Analyses

This paper covers two key aspects concerning slope analysis and design. In the first part, different analytical methods are reviewed and a method of limit equilibrium slope analysis that allows the interslice force inclinations to vary is presented. The new approach (referred to as the Arup Method), applicable on both circular and non-circular slips, is a further refinement on the popular Bishop and Janbu methods and is designed to overcome the numerical difficulties stemming from interlock. The proposed approach achieves overall horizontal, vertical and moment equilibrium of the slope, while also keeping every slice in horizontal and vertical equilibrium. Illustrative examples are presented to compare results from this method against recognized methods of analysis, including Morgenstern-Price, which employs a user-defined interslice force function. In the second part of the paper, development of a digitalised workflow for slope analyses and design is discussed and the authors demonstrate how customised coding enables optimisation of slope design involving soil nailing.