Otimização paramétrica de treliças planas e espaciais considerando restrições de flambagem e tensões

Abstract

Structural optimization enables the search for optimal solution through mathematical models, based on the objectives and conditions of the problem. Thus, by means of iterative processes, several combinations of possible solutions are analyzed, considering multiple criteria that influence the quality of results. The present work deals with the parametric optimization of truss structures aiming weight minimization. Stress, buckling constraints and maximum displacements are considered in the process, following the Brazilian standard NBR 8800:2008. The optimization is performed with a genetic algorithm, and the structural problem is solved using a finite element code, which evaluates the displacements, stress and buckling on each member. The results were compared with those selected by other optimization methods, which are available in literature. After an analysis of the results, the developed algorithm is effective because it was able to get close, equal or inferior results when compared to the other methods. When buckling constraints are considered the structure presents a significant increase in its weight.