Important factors that control the stability of rock slope are jointed discontinuities and water whereas, in soil the cohesion and water. Numerical modeling depends on both site conditions and the potential mode of failure. Numerical techniques can be applied to complex translational rock slope deformations where step-path failure necessitates degradation and failure of intact rock bridges along basal, rear and lateral release surfaces.
Initiation or trigger mechanisms may involve sliding movements which can be analysed using limit equilibrium theory. However, creep in rock, progressive deformation, and extensive internal disruption of the slope mass cannot determined by using limit equilibrium approach. The factors initiating eventual sliding may be complex and not easily allowed for in simple static analysis. Recent advances in the characterization of complex rock slope deformation and failure using numerical techniques have demonstrated significant potential for broadening our understanding of the mechanisms and the associated risk. Numerical modelling of slopes is now used routinely in the civil and mining engineering sectors as well as in academic research. The major benefits of numerical modeling are that
The advantages of a Numerical approach to slope stability analysis over traditional limit equilibrium methods can be summarized as follows:
(a) No assumption needs to be made in advance about the shape or location of the failure surface. Failure occurs `naturally' through the zones within the soil mass in which the soil shear strength is unable to sustain the applied shear stresses.
(b) Since there is no concept of slices in the numerical approach, there is no need for assumptions about slice side forces. Numerical method preserve global equilibrium until failure is reached.
(c) If realistic soil compressibility data are available, numerical solutions can give information about deformations at working stress levels.
(d) Numerical methods are able to monitor progressive failure including overall shear failure.
Basic outline in simulating the slope problem using numerical modeling
Important failure indicators in slope analysis