Efficient strategies for solving reliability-based optimization problems

Reliability-based optimization (RBO) is a powerful tool for design, as it allows to determine an optimal structural configuration while explicitly taking into account the effects of uncertainty (loading, geometry, structural parameters, etc.) on the structural performance. Nonetheless, the practical application of RBO to problems of engineering interest may be rather involved, due to the necessity of repeatedly computing the structural response for different sets of the uncertain parameters and design variables. This contribution proposes a framework for performing reliability-based optimization efficiently. The proposed approach, based on a decoupling approach and sequential approximations, introduces two new techniques: a line search strategy and weighted approximations. An application example involving a non linear structure under dynamic loading is presented, showing the advantages and efficiency of the proposed framework.