Characteristics of unsteady pressures on slender tall building

This paper investigates the characteristics of unsteady pressures on a vibrating model under low-turbulence and boundary-layer flows. Large and clear differences between static and vibrating models were found in the across-wind direction, but only small differences were found in the along-wind direction. The fluctuating generalized force coefficients of the vibrating model were larger than those of the static model, showing the largest value near the resonant wind speed. Two peaks in power spectra of the generalized force coefficients, the Strouhal component and the natural frequency component, were observed during the lock-in range. The cross-correlations of pressure coefficients became small and the time lag differences became large with increasing wind speed.