Experimental study on cold-formed steel shear walls with a self-centering energy-dissipation brace

The existing research outcomes reveal that, in contrast to cold-formed steel (CFS) shear walls cladded with traditional materials such as plywood, Oriented Strand Board (OSB), and flat steel sheets, CFS shear walls with corrugated steel sheathings exhibit significant improvements in both shear capacity and initial stiffness. Furthermore, the inherent non-combustibility of this material ensures enhanced fire performance for the structure. Nevertheless, the ductility and deformation capacity of the shear walls with corrugated steel sheathings are relatively poor. The degradation of the strength and stiffness of the structure accelerates after the peak point, and the residual deformation under cyclic loading is relatively considerable, restricting the safety and application of the structure. To address these issues, a self-centering energy-dissipation brace (SCEDB) is introduced into the CFS shear wall system. Through the energy dissipation and self-resetting functions of the brace, the energy dissipation capacity and the ductility of the wall are expected to be improved. A reduction in the residual deformation of the wall would also be achieved. Based on the introduction of the configuration and working mechanism of the brace, tests on eight CFS shear walls with corrugated steel sheathings are conducted in this paper. The influences of the initial parameters such as the presence or absence of the brace, and the prepressure of the brace on the seismic performance of the wall are compared. The results indicate that after the installation of the SCEDB, the bearing capacity, stiffness, ductility, and energy dissipation capacity of the wall are all significantly enhanced, and the residual deformation is substantially reduced. Additionally, the residual deformation of the wall under cyclic loading is closely related to the initial pre-pressure of the brace. When the preload of the brace exceeds the friction load, the residual deformation of the shear wall decreases significantly.