Time-variant system reliability

An efficient simulation-based methodology for estimating the time-variant reliability of redundant structural systems is presented in this paper. The proposed solution methodology, without much extra effort, is able to include the effect of resistance degradation as well as information about the periodic repair of a system in arriving at a reliability estimate. In the proposed method, the branch and bound method is used to identify only one failure sequence of the system, This defines the initial failure domain to start the simulation. As the simulation progresses, the initial failure domain is refined adaptively to incorporate information about the other possible dominant failure sequences, to estimate the true failure probability of the system. The proposed method is also quite efficient in estimating the reliability of ductile structural systems in the time-independent domain.