异型网架结构分级优化方法及其工程应用

A MULTILEVEL OPTIMAL METHOD AND ITS ENGINEERING APPLICATION FOR HETEROTYPIC SPACE GRID STRUCTURE

异型网架结构具有受力复杂、形体变化大和结构参数相关性强等特点,导致该类结构的优化分析一直是研究的难点。从异型网架结构的几何特征和受力特点出发,以异型网架结构重量最轻为优化目标,提出适合于异型网架结构的分级优化模型,即第一级基于网架结构的局部约束,进行满足杆件强度和稳定的截面优化;第二级基于网架结构的整体约束,完成结构位移和整体稳定等优化。将离散变量优化和相对差商法进行结合,给出了适应于异型网架结构分级优化的计算方法。基于上述研究成果,应用ANSYS软件及其参数化语言,编制了异型网架结构的分级优化程序。以某实际工程为研究对象,通过与网架设计通用软件MST的计算结果比较,表明并验证了该文异型网架结构分级优化方法的有效性和实用性。

The heterotypic space grid structure（HSGS） is featured with complex mechanical behavior, a variable structural shape and a strong correlation relationship among structural parameters. HSGS＇s optimization has always been a challenging subject. By studying geometrical characteristics and mechanical behavior of HSGS, a multilevel optimization method was proposed to minimize the HSGS weight. In the first stage, the strength and stability of HSGS members were optimized in the local constraint. In the second stage, the overall stiffness and stability of HSGS were optimized in the overall constraint. The computational optimization method for HSGS was realized by combining the discrete variable optimization design theory with the relative difference quotient algorithm. The multilevel optimization method of HSGS was programmed by using the ANSYS parameterized language. The validity of the optimization method and program were testified by comparing the results of a real engineering case from the multilevel optimization method with the results of the MST software.