Ⅰ型截面框架结构基于可靠性的优化设计

Reliability-based Optimization Design for Ⅰ-type Section Frame Structure

以结构系统的可靠度作为结构优化设计的控制参数．用改进的分枝限界法判认主要失效模式，用ＰＮＥＴ法计算结构系统的可靠度．结构可靠性分析中考虑了轴力效应．导出了平面框架结构可靠度的灵敏度分析表达式．提出最佳矢量型算法，有效地求解了Ⅰ型截面框架结构在系统可靠度约束下的最小重量设计问题；且在其中通过变量连接考虑了薄壁梁的稳定性要求．计算了若干例题，其结果说明了方法的有效性．

In this Paper,the reliability of structural system is regarded as the control parameter for the structural optimization design.The significant modes are identified by using the branch-and-bound method.The reliability of structural system is evaluated by PNET method.The axial force effects are regarded in the structural reliability analysis.The expression of sensitivity analysis for the plane frame structural system reliability is derived.An optimum vector algorithm is presented to solve the problem of minimum weight design with the constraint of Ⅰ-type section structural system reliability.The stability of the thin plate is regarded by design variable link.Several examples are evaluated,and the results demonstrate that the method presented in the paper is effective.