Wind-induced vibration control of tall buildings using hybrid buckling-restrained braces

A buckling-restrained brace (BRB) is a system with excellent earthquake-proof performance, but it does not dissipate energies caused by the load from weak earthquakes or winds. A hybrid BRB (H-BRB), which improved the performance of the BRB, is a type of composite damper system consisting of a BRB and a viscoelastic damper. To explain the wind-induced vibration control performance of H-BRB, a 40-story steel building was designed and used as an analysis model in this study, on the basis of the damping ratio from a structural performance test, using normal steel braces, BRB and H-BRB. In addition, to evaluate the optimal location of H-BRB, a time-history analysis of four models was conducted in the study. For such time-history analysis, wind-load data in a 10-year recurrence interval, which were calculated from the wind tunnel test, were used. The result of the time-history analysis showed that H-BRB is effective in improving both the lateral stiffness and serviceability of a building using the existing BRB. It also confirmed that it is most effective to position H-BRBs mainly on the lower stories.