Optimum weight design of steel truss roof systems considering corrosion effect

In this paper, the ideal weight for steel truss roof systems is determined while corrosion is considered. Because one of the most crucial problems that steel truss roof systems may experience during their service life is the effect of corrosion. If a corroded structure is designed without considering this effect during the design phase, significant damages and even collapses may occur before it reaches its service life. For this reason, the aim of this study is to make weight optimizations by considering the corrosion effect of steel truss roof systems. Thus, it has been revealed how corrosion that may develop on the truss members' surfaces affects the structure's overall optimum weight. Swarm intelligence-based algorithm approaches, Ant Colony Optimization (ACO), and Butterfly Optimization Algorithm (BOA) are used for this purpose to determine the optimal weight design of five different steel truss roof systems that were previously researched. The main program, which includes structural analysis (FEA) and optimization algorithms, is coded in the MATLAB programming language. The compression and tension bars selected as the limiting functions of the optimization problems are obtained from the stress, displacement, and slenderness conditions specified in the American Institute of Steel Construction-Allowable Strength Design (AISC-ASD, 1989) standard. It is seen that the optimum weight results obtained from all optimization methods for each structure in the non-corrosive condition are relatively similar. This result proves the correctness of the algorithms proposed in this paper. Then, under the influence of corrosion, the optimal weight designs of the structures are carried out. When the findings for the two cases are examined, it can be seen that the optimum weight values for all structures have slightly increased. This is because larger profiles are required due to overcapacity brought on by section loss. The weight of the structure increases in lockstep with the severity of corrosion. All the results like this are presented in detail with the help of tables and graphs in the relevant sections.