【摘要】 以SRC框架-RC核心筒混合结构多目标优化设计为研究背景,通过引入损伤函数,将结构的工程造价和损伤量最小定为优化目标,并根据建筑结构"三水准"抗震设防的目标要求,以及结构在不同受力阶段各类构件的受力特点,提出三水准优化设计的方法:小震作用下,认为混凝土处于开裂的临近状态,假定钢材未发挥作用,仅有混凝土发挥作用,据此对结构构件的截面尺寸与混凝土用量进行优化;在中震作用下,框架与剪力墙处于协同工作状态,据此对整个结构满足层间位移差最小之目标的钢材用量进行优化;在大震作用下,结构处于塑性状态,剪力墙基本退出工作,据此对满足结构损伤值最小之目标的钢材用量进行进一步的优化。从而将一个多目标优化问题转化为多个单目标优化问题求解。综合考虑各种约束条件,运用遗传算法与准则优化法的结合(亦即OC-GA混合算法),实施SRC框架-RC核心筒混合结构基于失效模式的三水准优化求解。通过引入一个24层SRC框架-RC核心筒混合结构的设计实例,对结构优化后的有限元模拟结果进行分析,证实了该优化设计思路是有效、可行的。更多还原

【Abstract】 Multi-objective design of a SRC frame-RC core wall hybrid structure was taken as an example,minimizing its project cost and damage was taken as optimization objectives by introducing a damage function. According to the three-level aseismic fortification criterion,and the mechanical characteristics of the structure,a three-level aseismic fortification criterion optimization design method was presented. The optimization of the cross-section sizes of the structural components and concrete volume was actualized by assuming that only concrete works under a minor earthquake. The optimization of steel volume was performed to meet the requirement of the minimum displacement difference between two adjacent storeies under a moderate earthquake,while the frame and shear wall were in a collaborative working state. The optimization of steel volume was implemented further to meet the requirement of the minimum structural damage under a severe earthquake,while the structure was in a plastic state and the shear wall was out of work. So,a multi-objective optimization problem was converted into several single-objective optimization problems. Taking various constraints into consideration,a failure modes-based three-level aseismic optimal design of a SRC frame-RC core wall hybrid structure was actualized by using the combination of the genetic algorithm and the optimization criterion,i. e.,the OC-GA algorithm. A numerical example of a 24-storey SRC frame-RC core wall structure was analyzed to verify the rationality of the proposed method.更多还原