A novel brace-damper system for seismic response suppression of high-rise steel frame structures

Chevron-brace-damper systems (CBDS) have been widely used in frame structures. To improve the performance of CBDS, a hybrid of the chevron and scissor-jack brace-damper system (C-SJBDS) is proposed. The relationship between the inter-storey drift and viscous damper (VD) axial deformation is derived, and the non-linear response of the VD is analysed. Applying the instance and bar element models of CBDS and C-SJBDS to the dynamic analysis of a plane steel frame structure validates the derivation of the theoretical model. Subsequently, a dynamic analysis is performed for 10- and 20-storey steel frame structures, with five typical ground motions. The results indicate that structures involving C-SJBDS, compared with the uncontrolled structures, the peak displacement at the top is reduced by approximately 15–65%, the inter-storey drift angle is reduced by approximately 30–90%, and the storey shear force is reduced by approximately 35–95%, which are lower than those involving CBDS by approximately 10–45%, 5–45%, and 5–50%, respectively. A further evaluation is implemented, through the energy analysis, and the results indicate that C-SJBDS has a good ability to dissipate energy, which is more than that of CBDS by approximately 10–40%. Finally, the parameter analysis of C-SJBDS is conducted, its results indicate that both the angle between bar and horizontal direction and the length of longer diagonal for the diamond mechanism will affect the structural response; these parameters should be designed reasonably before engineering applications. The whole presentation proves that C-SJBDS is a stable, safe, and efficient energy dissipation system for building structures.