Development of optimum design method for composite building structures using structural walls with hysteretic dampers

通过对复合结构墙体的试验研究，提出了一种由倾覆力矩产生的新型倒塌机理，得出以下结论：(1)制作了4种设计为倾覆破坏机制的复合墙体，并在循环侧向荷载条件下进行了试验。从基本准则（即刚度、强度和能量吸收能力）的角度来看，它们中的三个表现出令人满意的方式。钢管混凝土柱底部的塑性铰未出现任何剪切破坏迹象。(2)墙体试件中的连梁在小层漂移处屈服，吸收了大量能量，但外观损伤不严重。结果表明，h型钢连接梁可以起到滞回阻尼器的作用。(3)在两个开框试验中观察到，受方钢管约束的钢筋混凝土柱在强震作用下表现出延性和稳定性，无损伤，无需修复。从基于性能的设计理念的角度来看，如果结构墙阻止了软层机制，那么在强烈地震期间没有理由避免柱铰接。(4)本研究分析阶段采用的分析方法能够以合理的精度预测墙体试件的行为。

The following conclusions are reached on bases of the experimental study on the composite structural walls developing a new type of collapse mechanism generated by overturning moment.(1)Four types of composite walls designed to be failed in overturning collapse mechanism were fabricated and tested under the cyclic lateral loading condition. Three of them behaved in a satisfactory manner as expected from a view point of the basic criteria, i.e. stiffness, strength, and energy absorption capacity. Indications of any kinds of shear failure were not observed in the plastic hinges developed at the bottoms of the concrete filled steel tubular columns.(2)The coupling girders in the wall specimens yielded at the small story drift, and absorbed a large amount of energy without a severe damage in appearance. It is concluded that the H-shaped steel coupling girders can take a role of the hysteretic damper.(3)It was observed in the test of the two open frames that the reinforced concrete columns confined by the square steel tube behaved in a ductile and stable manners without damage to be repaired after a severe earthquake. There is no reason for avoiding column hinging during a severe earthquake from a view point of performance-based design philosophy, if the soft story mechanism is prevented by the structural walls.(4)The behavior of the wall specimens can be predicted with a reasonable accuracy by the analytical method used in the analytical phase of this study.