Damage-Control Systems Using Replaceable Energy-Dissipating Steel Fuses for Cold-Formed Steel Structures: Seismic Behavior by Shake Table Tests

摘要

A system that controls the rocking behavior of multistory shear walls is proposed as an innovative damage-control system for cold-formed steel structures. In this system, we have developed a new hold-down equipped with a fuse function (HDF) that controls the rocking behavior and is placed on the foundation of multistory shear walls. The HDF contributes to reducing damage to both structural and nonstructural members in cold-formed steel framed buildings, dissipating seismic input energy in the event of a large earthquake. The present paper describes the shake table tests performed using one-story, one-span, real-size specimens to investigate the fundamental behavior of the developed system. By using shake table tests in which the type of hold-down and the magnitude of input ground motion were varied as parameters, it was clarified that the plasticization of HDFs could reduce the base shear of specimens and that the energy dissipation by the HDFs could subdue the uplift deformation of the specimens. It is also shown that specimens that were not connected with foundations had the least base shear, but their uplift deformation was difficult to control because of their rocking-free condition. Overall, it was shown that incorporation of HDFs was effective in both reducing the base shear and controlling the rocking behavior in a stable manner.