In this article, an efficient methodology is developed to optimize nonlinear steel frames under several load combinations. For that purpose, inelastic advanced analyses of steel frames are performed using plastic hinge beam–column elements to reduce computational efforts. An improved differential evolution (DE) algorithm is utilized as a global optimizer to refine the solution accuracy and enhance the convergence speed. Compared to the conventional DE algorithm, this newly developed method provides four major improvements such as: (1) a new mutation strategy based on the p-best method; (2) the multi-comparison technique (MCT) to decrease the number of unnecessary objective function evaluations; (3) a promising individual method (PIM) to choose trial individuals; and (4) a trial matrix containing all evaluated individuals to avoid objective function evaluations of duplicate individuals. Furthermore, panel zones are taken account of optimum design for the first time. Doubler plates are designed to prevent panel-zone shear deformations. Three mid- to large-size steel frames considering several load combinations required by AISC-LRFD are considered. Five new and efficient meta-heuristic algorithms are employed for comparison.

在本文中，开发了一种有效的方法来优化几种载荷组合下的非线性钢框架。为此，使用塑料铰链梁柱单元对钢框架进行了非弹性高级分析，以减少计算量。改进的差分进化（DE）算法被用作全局优化器，以改善求解精度并提高收敛速度。与传统的DE算法相比，这种新开发的方法提供了四个主要改进，例如：（1）基于p-best方法的新变异策略；（2）多重比较技术（MCT），以减少不必要的目标函数评估次数；（3）选择有前途的个人的有前途的个人方法（PIM）；（4）包含所有被评估个体的试验矩阵，以避免重复个体的客观功能评估。此外，面板区域首次考虑了最佳设计。双层板的设计可防止面板区域的剪切变形。考虑了三个AISC-LRFD要求的几种载荷组合的中大型钢框架。五个新的高效元启发式算法用于比较。