Abstract:There are too many variables in the optimization design of the truss girder structure with bulge formed joint. Besides, the scale of the optimization is large. In addition, the calculation is complex and the convergence is not suitable if the integral monolayer optimization strategy is adopted. In order to solve these problems, a hierarchical cooperative optimization strategy based on subspace and coupling constraints has been proposed. The design space is divided into three subspaces， which are the whole layer, the section layer, and the surface optimization layer. The upper layer provides the optimization results for the lower layer while the lower layer provides the coupling constraint for the upper layer. The result shows that the optimization method can get good results and has some engineering significance.
