基于遗传算法的预应力钢桁架优化设计

目的针对预应力钢桁架的结构截面变量取值离散性、设计需考虑多种因素影响、计算重分析次数较多等特点，应用遗传算法对其进行优化设计，从而达到使结构受力合理，质量最轻的目的．方法通过有限元方法对预应力钢桁架结构进行结构分析，得到相应的应力、内力，然后按照一定的优化模型对结构进行遗传操作，得到优化结果．结果应用所编程序对平面预应力钢桁架实例进行优化设计，算例表明相对于其他优化算法，遗传算法在预应力钢桁架的优化设计中具有可行性和有效性．结论所编程序具有编程简单、快捷、搜索效率和求解精度较高等特点，克服了已有工程实践中通过多次试算，按经验来确定预应力值的弊端，为预应力钢桁架的优化设计提供了一种可行的方法．

Optimization Design of Pre-Stressed Steel Trusses Using a Genetic Algorithm

In order to make the structure reasonable and the weight light,genetic algorithm is applied for optimization of pre-stressed steel trusses in the paper.The program of optimization is regimented based on the characteristics of prestressed steel trusses and genetic algorithm.The stress and internal force are computed,according to finite element method.The algorithm is operated in the light of optimization model.The result of optimization is given out in term of optimal model and genetic operation.Comparing with other method,genetic algorithm is in possession of astringency and stability.The traits in the program are simple,shortcut,the higher of searching efficiency and computing precision.It overcomes the shortcomings of establishing the value of pre-stressed by experience.A new method of optimization design of pre-stressed steel trusses is put forward in the paper.