Optimum design of thin-walled closed cross-sections: a numerical approach

In this paper, the problem of optimum design of a thin-walled closed cross-section is presented. The problem consists in minimizing the material area of a thin-walled closed cross-section symmetrical with respect to both x and y centroidal axes, and subjected to flexural and torsional rigidity constraints and strength constraints. The unknown function is the middle line of the thin-walled closed cross-section while its thickness is t prescribed. The solution approach is numerical and the minimizing procedure is based on an improved simulated annealing method, a simple but robust direct search technique that works well on fast PCs.