Evaluation of wind-induced fragility and cumulative fatigue damage on seismically isolated high-rise building

Abstract

Seismically isolated buildings (SIBs) are built higher and higher for which wind-induced effect is of worldwide concern. To comprehensively study this effect, this paper proposes a theoretical framework of wind-induced fragility evaluation for SIBs. A Chinese seismically isolated high-rise engineering building is systematically evaluated as a case study. The probability wind load demand model for SIBs is developed. The wind-induced performance evaluation indices set according to different national codes are assessed and compared from a probabilistic perspective. A parametric analysis is conducted to explore a reasonable range of values for wind load partial factor. The cumulative fatigue damage at seismic isolation interface (SII) under extreme wind loads is investigated. Results show that SIB can generally meet performance requirements for lateral stiffness. The performance evaluation indices under 1-year return period wind load are more demanding than those under 10-year return period wind load. The value of wind load partial factor is recommended to be within the range of 1.4–1.6 for sufficient wind-resistance stability without compromising seismic reduction performance. The LRB used in SII not only provides wind-resistance stability, but also perform well in resisting wind-induced fatigue damage. Nevertheless, periodic inspections are necessary to assess wind-induced residual deformation at SII.