Multiobjective Optimization of prestressed composite steel and concrete beam via non-dominated sorting genetic algorithm (NSGA)

Resumo

The use of prestressing in steel beams and composite steel and concrete beams is still underexplored in the design of structures with large spans due to the lack of specific normative codes for this type of structural element. Studies involving optimization techniques for these types of structures are scarce in the literature, thus opening up a vast field of research to be explored. This study aims to propose the formulation of a multi-objective optimization problem for composite steel and concrete beams with external prestressing. The final cost of the beams, CO2 emissions from the materials used in their fabrication, and the maximization of the payload that the beam can support are considered minimization objectives. Constraints include the requirements for composite steel and concrete elements from NBR 8800:2008 and the prestressing provisions from NBR 6118:2021. The non-dominated sorting genetic algorithm (NSGA) from the Matlab package will be used to solve the optimization problem. Examples demonstrating the solution's effectiveness will be compared with examples from the literature, and Pareto frontiers will be evaluated to verify the best solutions for the proposed problems.