Optimal Design of Reinforced Concrete Frame Structures Using Cascade Optimization Method

Abstract

Optimal design of structures is one of the goals of a structural engineer. Since a large number of design variables are involved, the high computational time for optimization process is one of the main problems of using single heuristic or meta-heuristic algorithms utilized for this purpose, especially in large-scale structures. Cascade optimization replaces the single optimization problem with a multiple stage process. Each step starts with the previous optimum design, with the number of variables being reduced thus increasing the speed of the convergence in each stage of optimization. In this article a Cascade optimization method is developed for optimum design of RC frame structures. By using this algorithm in place of a single optimization method and ensuring its efficiency, the optimum section dimensions are determined by a new method. Then, genetic algorithm is utilized for optimizing of rebar arrangement. According to the results, this method performs optimum design and reduces the elapsed time considerably. Optimization of large-scale concrete structure is carried out by the developed method. It should be noted that the present method works with MATLAB and ETABS interfacing.