A replaceable sandwiched metallic fuse damper for seismic protection of braced frames

In this study, a replaceable Sandwiched Fuse Damper referred to as SFD is introduced to enhance the seismic performance of braced frames. The SFD consists of one or several fuses made by Hollow Structural Section (HSS), sandwiched between two steel plates. The fuses are welded to the steel plates in a parallel pattern. An axial force in a brace equipped with the SFD imposes a relative movement on the steel plates welded to the fuses. The fuses yield as a result of such relative movements and dissipate the input energy. In contrast to other metallic dampers, the fabrication and installation of the SFD are much simpler, resulting in lower construction and maintenance costs. The seismic performance of the SFD was investigated through a series of displacement-controlled cyclic tests, in which the SFD was installed within a brace and its cyclic response was compared with that of the bare brace. The experimental results showed that the SFD-brace system possessed stable hysteresis loops, a large deformation capacity, and an excellent energy dissipation capacity. An analytical model was developed to estimate the SFD's yield strength and its corresponding displacement. Experimental results were employed to examine the efficiency of the proposed model. It was shown that the yield strength of tested specimens was estimated with good accuracy.