Reliability-based optimization considering design variables of discrete size

This contribution presents an approach for performing reliability-based optimization (RBO) with emphasis on the treatment of discrete design variables. The key idea of the proposed approach is the construction of an approximate representation of the structural reliability (i.e. a meta-model for reliability). This allows replacing the original RBO problem with a series of approximate yet accurate subproblems. These approximate subproblems can be solved most efficiently using any appropriate optimization method. Application examples involving the design of steel frames illustrate the features of the proposed approach.