包容式节点桁架多目标分层优化设计

Multi-objective Hierarchical Optimization of Truss Girder Structure with Bulge Formed Joint

摘要:

针对包容式节点桁架优化设计变量多、优化问题规模大，采用单层混合优化策略计算量大且不易收敛的问题，提出基于子空间和耦合约束的分层协同优化策略，将设计空间分为三个子空间，分别是整体层、截面层和曲面形状优化层，上一层优化结果为下一层提供输入量，下一层为上一层提供耦合约束；对设计变量进行灵敏度分析，确定各个优化层的目标函数和约束条件.结果表明，该优化方法能够较好地处理具有层次关系的工程优化问题.

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.