摘要
针对传统复杂截面结构寿命期优化效率低及未考虑结构劣化效应的问题,将传统的直接以结构基本尺寸为优化变量的计算方案改为分3步优化:首先选取与截面造型无关的构件截面面积、抗弯惯矩、上下边缘距横截面中性轴的距离为中间变量,分别获得可靠度约束下的最优值,继而基于第一步优化结果,优化达到寿命期时所需的与构件造型有关的基本设计尺寸,最后考虑寿命期劣化效应的影响,逆向推算得结构初始设计尺寸。新型优化方案通过以构件共有的几何参数为中间变量,减少了复杂截面优化过程中直接以设计变量进行迭代的工作量,提高了优化效率及优化模式的适用性。寿命期劣化效应的考虑兼顾了优化模型的耐久性.效率。
Aiming at solving the low efficiency and the ignorance of the structural deterioration effect of the traditional complex cross-section structure, the traditional direct optimization method based on the structural basic dimensions are divided into three steps. Firstly, we select the cross-sectional area, the bending moment of inertia, the distance between the upper and lower edges from the neutral axis of the cross-section as the intermediate variables, which are unrelated to the type of cross-sectional. So the optimal value under the constraint of reliability will be respectively obtained. Secondly, the basic dimensions based on the optimization results of the first step are optimized. Finally, we calculate the initial design size of the structure in reverse in consideration of the effect of life span deterioration. The new optimization scheme can reduce the workload of directly iterating the design variables in the process of optimization of complex sections. It can also improve the optimization efficiency and the applicability of the optimization mode. By consideringthe deterioration effect of lifetime and the durability of the optimized model, the accuracy and efficiency of the new optimization model are verified by comparing it with the traditional optimization model.
引文
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