A hybrid optimization algorithm for the optimal design of laterally-supported castellated beams


Centre of Excellence for Fundamental Studies in Structural Engineering, Iran University of Science and Technology, Narmak, Tehran, P.O. Box 16846-13114, Iran


In this paper a hybrid method is developed for optimum design of castellated beams by combining two meta-heuristic algorithms, namely the colliding bodies optimization (CBO) and particle swarm optimization (PSO). In this hybrid algorithm (CBO-PSO), positive features of PSO are added to the CBO. Two common types of laterally supported castellated beams are considered as design problems: beams with hexagonal openings and beams with circular openings. These beams have found widespread usage in buildings because of great savings in materials and construction costs. Here, the minimum cost is taken as the design objective function and the new hybrid method is utilized for obtaining the solution of some benchmark problems. Comparison of the results of the CBO-PSO with those of some other metaheuristics demonstrates the capability of the presented optimization algorithm. For most of the examples, the results obtained by the CBO-PSO have less cost in comparison to those of the other considered methods. It is also concluded that the beams with hexagonal openings require smaller amount of steel, hence being superior to the beams with cellular openings.