Seismic design framework for steel structures with hysteretic and viscous dampers

Mixed-use of viscous and hysteretic dampers is considered an effective way to control the seismic responses of nonlinear building structures; however, the existing damper capacity design methods were mainly constructed based on a single type of damper. In this study, a displacement-based design method is proposed to determine the capacities of the two types of dampers simultaneously. The equivalent stiffness of the added component and the primary structure at the target drift is considered vital factors. Based on the assumption that the equivalent stiffness is proportional to the shear force, the stiffness of the added component can be derived, which further determines the capacity of the dissipative damper. The seismic control design and nonlinear time history analysis were performed on ten-story steel moment frame buildings with different structural parameter settings, and six scenarios of damper arrangement were compared. It was demonstrated that the proposed procedure could derive a design scheme for an arbitrary damper arrangement to achieve a relatively uniform story drift in structure. The fragility analysis was further performed to compare the seismic control effect of various damper arrangement schemes for comprehensively understanding their performance.