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

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.

Key words:coupling beam; fuse; low cyclic reversal test; hysteretic behavior; fatigue properties