Optimization of CO2 emissions of composite alveolar beams considering manufacturing constraints

Abstract The increasing concern over the scarcity of natural resources has driven the search for more sustainable structural designs. Among the various alternatives, steel-concrete composite cellular structures have emerged as a good solution for large spans, combining the strength properties of concrete and steel without significantly increasing the structure's mass. This article presents a formulation for the optimization of steel-concrete composite cellular beams aimed at minimizing carbon dioxide (CO2) emissions. In addition to the materials used, emissions from manufacturing processes, specifically cutting and welding of profiles, are also considered. The problem was addressed using Particle Swarm Optimization (PSO) and the Grey Wolf Optimizer (GWO), and numerical examples are provided to investigate the advantages of the proposed formulation compared to steel welded beams. Among the results, it was observed that similar solutions were obtained with both optimization methods. In addition, varying the span of the beams in a range of 5 to 17.5 m, it was possible to identify structural profiles and configurations that are more efficient regarding weight and environmental impact. The best results in almost all the spans are from the Litzka beam, except for the 17.5 m span, which was the Peiner beam that had the lowest CO2 emission.