In this paper, a new algorithm is proposed to multi-objective optimum seismic design of steel moment frames. This algorithm is based on the uniform damage (also known as uniform deformation) theory and so-called multi-objective uniform damage optimization (MUDO). MUDO is a swift algorithm formulated according to a bi-objective approach. Structural weight and maximum interstory drift ratio (IDR) are treated as two conflicting objectives representing economy and safety measures, respectively, and they are minimized simultaneously subject to a set of design constraints. To achieve the optimal Pareto front, MUDO tries to create a uniform distribution of story drifts in the structure and bring it to a target value that gradually varies from the low (minimum damage) to high (maximum damage). In this way, the algorithm obtains a set of optimal solutions in terms of structural weight at different damage levels, which is the Pareto front. To demonstrate the efficiency and robustness of the proposed algorithm, its results for 3-, 6- and 9-story steel moment frames are compared with those of two well-known multi-objective optimization algorithms, NSGA-II and MOPSO. Results indicate that MUDO can achieve better optimal solutions set in a much less computational time than the other two methods.

提出了一种新的钢矩框架多目标最优抗震设计算法。该算法基于均匀损伤（也称为均匀变形）理论和所谓的多目标均匀损伤优化（MUDO）。MUDO是根据双目标方法制定的快速算法。结构重量和最大层间漂移率（IDR）分别被视为代表经济和安全措施的两个相互矛盾的目标，并且在受到一系列设计约束的同时将它们最小化。为了获得最佳的帕累托锋线，MUDO尝试在结构中创建故事分布的均匀分布，并将其达到从低（最小损害）到高（最大损害）逐渐变化的目标值。这样，该算法获得了在不同损伤水平下的结构重量方面的一组最优解，这是帕累托前沿。为了证明所提算法的效率和鲁棒性，将其在3层，6层和9层钢结构框架中的结果与两种著名的多目标优化算法NSGA-II和MOPSO的结果进行了比较。结果表明，与其他两种方法相比，MUDO可以在更少的计算时间内获得更好的最优解集。