Reliability evaluation of rock wedge stability with correlated failure mode by SCM

In this paper, a reliability evaluation of rock wedge stability with correlated failure mode is presented. A cut-set system is employed to model the system aspects of the problem. The correlations between failure modes are calculated by defining equivalent linear safety margin for each failure mode and the system reliability index is evaluated by Sequential Compounding Method (SCM). An example case is analyzed to illustrate the proposed approach. The system reliability indices and corresponding probabilities of failure from the proposed method are compared with those of the Monte Carlo simulation (MCs). The results demonstrate that the probability of failure will be overestimated if the correlations between different failure modes of the wedge are not taken into account. Reliability sensitivity analyses are carried out to study the effect of changes in variables on the stability of the wedge. The results are highly dependent on the selected sensitivity analysis level.

Keywords:

Rock wedge stability , Sequential compounding method , Cut-set system , Correlated failure modes , Monte Carlo simulation