ABSTRACT
Rock slopes containing highly persistent discontinuities or discontinuity sets (i.e. bedding or foliation planes, faults) having parallel or sub-parallel inclination to the slope face are designated as footwall slopes. These slope types commonly form in weak, thinly bedded, orthogonally jointed, sedimentary rock environments. Although it has been suggested to use conventional kinematic rock slope stability techniques for footwall slopes, they are not readily analyzed using these methods since the discontinuities do not daylight on the slope face (due to having similar inclination as the slope face). In this study, slope stability analyses are conducted using 2D and 3D limit equilibrium (LE) and the finite element (FE) based method shear strength reduction technique for a theoretical fully and partially discontinuity controlled bi-planar failure mechanism. The advantages and disadvantages of using 2D-3D LE and FE-based methods in bi-planar failure analysis highlighted in the paper.
