Probabilistic Analysis of Rock Slopes Against Block Toppling Failure: Fid-Bau Portal

Probabilistic Analysis of Rock Slopes Against Block Toppling Failure

Roy, Debasree / Maheshwari, Priti

Abstract In the present paper, a probabilistic analysis procedure and related algorithm for the stability of rock slopes against block toppling failure have been developed using Monte Carlo simulation. For this purpose, first the deterministic model has been developed considering the presence of external loads and moments on the slope having non-orthogonal discontinuities. The discontinuity parameters (such as discontinuities orientations, friction angles) and seismic coefficient have been taken as normally distributed variables whereas spacing of discontinuities and pore water pressure have been considered as log normally distributed variables. The realizations of all the variable parameters, generated by central limit theorem, have been fed to the deterministic model for slope stability analysis. As a result, realizations of dependent variables [geometry, inter-block forces and factor of safety (FOS)] have been generated. Subsequently, the probability distribution function of FOS has been generated. Associated risk of slope failure in toppling for a particular value of FOS can be obtained. In addition, a comparative study has been performed to show the influence of external loads and moments on the stability of slope. External loads and moments have been found to have significant influence on the FOS and therefore probability of failure of rock slope.