Multi-Directional 3-D LEM Slope Stability

The limit equilibrium method (LEM) has been a main-stay of analysis for geotechnical engineers for decades. Applied typically in a 2-D plane strain condition the method has been extended in formulation to the method of columns in 3-D and is now gaining increased use in industry. The formulation of the 3-D method of columns has typically been presented in Cartesian coordinates and with the assumption that the slip direction is in the direction of positive or negative x-coordinates. This assumption severely limits the application of the method in a 3-D environment where the slip direction may be a searching parameter. This paper presents an extended 3-D solution method which allows solution of the 3-D method of columns at any slip direction. This extension will then allow the 3-D LEM to be applied to a broader class of typical geotechnical engineering calculations.