薄板结构加筋布局优化设计方法研究

提出一种两步优化策略，以加筋板结构的固有频率最大化为目标函数，以结构所受外载荷作用的最大静变形为约束条件，开展薄板结构加筋构件的布局优化设计研究。为了降低加筋布局优化的难度，提高优化设计的效率，将加筋等效为一系列弹性铰（点）支撑，以便快速获得加筋横向移动的灵敏度信息。在基本不改变结构重量的情形下，通过合理布局加筋位置，能显著改善结构的刚度分布，提高结构的整体承载能力。随后，小幅调整加筋的截面尺寸，以满足对结构最大变形的设计要求。最后，用两个算例验证了所提优化方法的可行性和有效性。

Layout optimization method for stiffeners of plate structure

A two-stage optimization method is proposed for optimal layout (position and size) design of stiffeners in a thin-walled structure.The design objective is to maximise of the structural natural frequency subject to the deformation constraint when the stiffened plate is loaded externally.First,for the purpose of a simple solution of the optimization problem,the stiffeners are modeled approximately as a series of elastic point supports such that the lateral movements of the stiffeners in the plate can be carried out efficiently upon the design sensitivity analysis.By the stiffeners'' movements,the natural frequency of the stiffened plate can be improved significantly while its weight is retained essentially in the position optimization process.Next,the stiffener sizes are redesigned to meet the static deformation constraint.It will be seen from the numerical examples that the proposed method for optimal stiffener layout design can work very well to enhance the structural mechanical properties.