Optimal design of reinforced concrete frames based on inelastic analysis

Abstract A new algorithm is presented for use in conjunction with the imposed rotation method as reformulated by Kaneko as a ( n × 2 n ) linear complementarity problem. The inelastic trilinear moment rotation law, which is modelled to reflect behaviour at critical sections, is adjusted during the incremental analysis in order to adhere the non-holonomic behaviour of reinforced concrete (RC) when stress unloading occurs. The algorithm is utilized in performing inelastic analysis for the optimal design of RC frames. Optimum concrete dimensions and reinforcement are evaluated for minimum cost. Optimization, following the multilevel approach, is carried out on typical frames using SUMT and Rosenbrock minimization methods.