Across and along-wind responses of tall building

KIM Young-moon¹, YOU Ki-pyo¹, YOU Jang-youl²

(1. Department of Architecture Engineering, Long-Span steel Frame system Research Center,
Chonbuk National University, Chonju 561-756, Korea;
2. KOCED Wind Tunnel Center, Chonbuk National University, Chonju 561-756, Korea)

Abstract:Most modern tall buildings using lighter construction materials are more flexible, which can lead to excessive wind-induced vibrations resulting in occupant discomfort and structural unsafety. It is necessary to predict and mitigate such wind-induced vibration at the preliminary design stage. Fluctuating across and along-wind loads acting on a tall building that could not be formulated theoretically were simulated numerically in the time domain using known across and along-wind load spectra. These simulated wind loads were used to estimate the across and along-wind responses of a tall building, which are less narrow-banded processes, based on the state space variable approach. The simulated across-wind response of root-mean-square value (0.0047) and that of KAREEM’s (0.0040) and the simulated along-wind response of root-mean-square value (0.021) and that of SOLARI’s (0.027) were compared. It is found that these are good approximations of closed form responses. Therefore, these numerically simulated across and along-wind loads can be used for across and along-wind responses estimation for the wind-resistant design of a tall building at the preliminary design stage.

Key words:across-wind load; along-wind load; across and along-wind responses; tall building