Spatial correlation of along-wind fluctuating wind loads on rectangular high-rise buildings

To investigate the effects of side ratio and turbulent characteristics on the spatial correlation of along-wind fluctuating wind loads on rectangular tall buildings, synchronization pressure wind tunnel tests for rectangular tall buildings with side ratios ranging from 1/9～9 were carried out in four wind fields. Based on the experimental findings, the coherence function and vertical correlation coefficient of along-wind fluctuating wind loads were examined in relation to the effects of side ratio, turbulence intensity, and turbulence integral scale. The mathematical model of vertical correlation of rectangular high-rise buildings with a side ratio of 1/9～9 was obtained by the nonlinear least square method. The results show that the correlation coefficient of along-wind fluctuating wind load is affected by both the side ratio and separation distance, and decreases exponentially with the increase of separation distance. The along-wind fluctuating coherence function decays exponentially with the increase of frequency, and the decay rate of the coherence function is roughly positively related to the ratio of separation distance to average wind speed. The effects of turbulence integral scale and turbulence intensity on the correlation of along-wind fluctuating wind loads are different for buildings with different side ratios. It can serve as a guide for structural design and load code revision since the coherence functions and correlation coefficients of along-wind fluctuating wind loads on rectangular high-rise buildings suggested in this work correspond well with the experimental data.