Methods of slope stability evaluation have varying complexities and data requirements. Kinematic methods are screening techniques that provide information on the structural feasibility of certain failure modes based solely on geometric data. Although it does not provide factors of safety, it is a highly useful technique for the initial evaluation of potential planar, wedge, or toppling failures.
Limit Equilibrium Methods (LEM) assess the stability of a slope based on a comparison of the forces of resistance and force of movement along a failure surface. LEMs yield a factor of safety and are preferred because of simplicity and acceptance by codes of practice. Nonetheless, LEMs involve assumptions about failure surfaces and do not account for stress redistribution or deformation.
Numerical analysis techniques such as finite element analysis and finite difference analysis can model the behavior and failure processes. These analysis techniques are most valuable in large pits, weak rock masses, and in the presence of groundwater and seismic forces. The disadvantage in this analysis technique is the large data requirement and processing time.
Usually, the best slope design integrates all the above methods where each method is most suited.
