Wind-induced response of high-rise buildings analyzed by different coherence functions of gust

Coherence function is an important parameter for describing the spatial-temporal correlation property of gust in wind engineering field. Based on the on site measurement and statistical analysis results, several expressions of coherence function have been put forward, which can be divided into two categories, considering the frequency effect or without considering the frequency effect. The precision of different coherence functions has been focused in the past, but the influence of different coherence functions on the wind-induced vibration analysis results has not been studied in details. In fact, it is more important to decide which expression should be adopted. In this paper, three common expressions of coherence function were introduced firstly, and the non-dimensional analytical solution of wind-induced vibration of high-rise structures was derived by random vibration theory in frequency domain. Then, the influence of frequency component on the wind-induced vibration analysis results was emphasized. The results indicated that resonant response is the dominative factor on the influence. Approximate 60% magnification would be induced by using the coherence function without frequency component, which is adopted by Chinese Loading Code. Finally, a reduction factor of 0.6-0.7 was given for calculating the fluctuation influence coefficient in Chinese Loading Code.