Reliability-based optimum seismic design of RC frames by a metamodel and metaheuristics

The present study is devoted to reliability-based optimum seismic design (RBOSD) of reinforced concrete (RC) moment frames within the context of performance-based design. A chaotic enhanced colliding bodies optimization (CECBO) metaheuristic algorithm is proposed to achieve the optimization task. In the framework of CECBO, chaotic maps are employed to achieve randomness that results in better convergence rate in comparison with its standard version. For reliability assessment of structures during the optimization process, the Monte Carlo simulation method is employed. In order to reduce the prohibitive computational burden of the MCS in the optimization setting, a metamodel is proposed to accurately evaluate the required deterministic and probabilistic structural seismic nonlinear responses. Efficiency of the proposed methodology for implementation of RBOSD process for RC frames is illustrated by presenting two numerical examples.