Characteristics of aerodynamic forces on high-rise buildings with various façade appurtenances

Abstract

The appurtenances effects of high-rise building on wind loads are investigated through a series of wind tunnel experiments with 21 façade appurtenances simulated by different configurations of horizontal splitter plates. “Zigzag variations” of layer forces can be found in both along-wind and cross-wind when the vertical separation distance ratio of continuous plates is larger than 4%. The appurtenances can significantly reduce fluctuating pressures on the side façade but with different effect on the fluctuating cross-wind layer force. The reason of this will be discussed in this study. The power spectra of response of the building model indicate that the horizontal façade appurtenances have negligible effects on the period of vortex shedding. But the peaks in the power spectra become slightly higher than those from a smooth surface model, and the bandwidths are also narrower. Such results indicate that the horizontal plates may result in better organization of the vortex shedding by restricting the flow in vertical direction and reduce the intensity of vortex. Further check on the correlation coefficients between pressures at the same level reviews that the correlation of response from different positions of the building models with appurtenances is higher than that for building model with smooth surface. It is also noted that discontinuous appurtenances can reduce the cross-wind base moment by approximately 5%.