可更换连梁保险丝抗震性能试验研究

Experimental study on seismic behavior of “fuse” of replaceable coupling beam

摘要:

联肢剪力墙是高层建筑结构中广泛采用的抗侧力结构体系，而连梁是联肢剪力墙结构中重要的耗能构件。传统的钢筋混凝土连梁通常由于跨高比较小，形成塑性铰耗能模式较难实现。更重要的是，连梁破坏后修复或更换非常困难，代价昂贵。近年来，国内外的部分学者提出了可更换连梁的概念即在连梁的跨中设置一个耗能构件，称之为保险丝，通过保险丝的塑性变形耗散能量，从而保护连梁的其余部分和与连梁相连接的墙肢部分免遭破坏。通过这种方式，在地震后对连梁的保险丝部分进行更换就比较方便。鉴于连梁的保险丝对连梁的耗能有着决定性的作用，本文提出了三种不同类型的连梁保险丝，通过低周反复加载试验对这三种保险丝的抗震性能进行了全面研究，比较了三种保险丝的滞回性能、强度和刚度退化性能、耗能能力和疲劳性能，最后提出了相应的设计建议。

Abstract:

Coupled shear wall structures are often employed as efficient lateral-force-resisting-systems in tall buildings，and the coupling beams are important members of dissipating seismic energy. The desirable energy dissipation mode of conventional reinforced concrete coupling beams is to produce flexural plastic hinge in the coupling beam end under earthquake. However, it is difficult to obtain desirable damage mode duo to smaller span to depth ratio of coupling beam. Moreover, the difficulties of postdamage repair or replacement are larger. Hence, over the past few years, the concept of providing a fuse in a coupling beam has been developed and investigated. The fuse is used to dissipate seismic energy and is easy to be replaced. Because the fuse plays an important role in energy dissipation, the writers develop three kinds of fuse. The seismic behavior of these fuses are investigated through low cyclic reversal tests in terms of the failure mechanism, hysteretic response, strength degradation, stiffness degradation, energy dissipation characteristics, and fatigue properties. Finally, the design recommendations of these fuses are also proposed.