Slope Stability Analysis

Assessing a slope’s stability is a challenging yet important aspect of civil engineering. In its simple form, limit equilibrium methods are used and stability is determined by the equilibrium of shear stress and shear strength. If the forces that resist the movement are greater than those driving the movement, the slope is considered stable. A factor of safety (FS) is calculated by dividing the resistance by the driving forces. A factor of safety greater than 1.00 suggests that the slope is stable. Slope stability analysis is implemented in numerous applications of civil engineering projects such as dams, embankments, excavated slopes, and natural slopes.

Slope stability involves both static and dynamic analyses. The stability techniques include limit equilibrium methods, empirical approaches for rocks slopes (SMR, Q-slope), finite element or finite difference methods, district elements codes, etc. The most common and practical method used is limit equilibrium, but it can prove to be inadequate when the slope experiences complex failure mechanisms (progressive failure, liquefaction, internal deformation or creep). In these cases, more sophisticated numerical models with advanced constitutive models should be utilized.