A Reliability Index Computation Method Based on Particle Swarm Optimization

For the structural limit state function with the multiple most probable failure points(MPP) and the multiple most probable failure domains, the reliability computation error generated by the First Order Reliability Method (FORM) or the Second Order Reliability Method (SORM) is unacceptable in some important project designs. The fundamental reason is that they only can obtain one design point and one most probable failure domain. An algorithm to find multiple MPPs with the particle swarm optimal method is proposed in the paper, and make a choice to estimate failure probability of structural limit state function based on the multiple most probable failure domains. The performance of proposed method is compared by the some difference methods. The results show proposed method is enough precise and effective.