## 4 Analysis of the Measured Fluctuating Wind Speed Data
### Turbulence Intensity  
A comparison of the three high-rises in terms of turbulence in the along-wind and across-wind directions (\(I_{u}\) and \(I_{v}\)) is shown in Figure 6. Before 9:00 am on 14 th September, the turbulence of buildings A and B was discrete, and the typhoon was far from the experimental building and had no effect on it at that time. The three high-rises had similar turbulence in the middle stage, but the turbulence of high-rise A increased in the late stage because the wind direction slowly moved northward, and a super high-rise is located north of high-rise A. This super high-rise produced an interference effect on the three high-rises. Figure 5: Comparison of the three high-rises in terms of their mean wind speed and direction with a time interval of 10 min. (**a**) Mean wind speed in 10 min; (**b**) Mean wind direction in 10 min. Figures 7 and 8 show the relationships between turbulence intensity and mean wind speed and between turbulence intensity and mean wind direction, respectively. The left side of the figures presents the synchronously recorded data of buildings A, B, and C. The right side of the figures displays the synchronously recorded data of buildings A and C when building B experienced power outage. The upper right corner of the figures exhibits the sample chart of wind speed and direction. The left side of Figure 7 shows that when \(U<10\) m/s, the turbulence intensity of buildings A and B decreases with the increase in mean wind speed, whereas the turbulence intensity of building C does not change with the increase in mean wind speed. When \(U\geq 10\) m/s, the turbulence intensity of the three buildings changes by the same law and decreases with the increase in mean wind speed. The right side of Figure 7 indicates that the turbulence intensity of building A increases with the wind speed. When the mean wind speed reaches 19 m/s, the turbulence intensity does not change with the increase in mean wind speed. When the mean wind speed reaches 25 m/s, the turbulence intensity decreases with the increase in mean wind speed. The turbulence intensity of building C decreases with  
Figure 6: Comparison of wind fields on the roofs of the three high-rises in terms of turbulence. (**a**) Longitudinal turbulence intensities; (**b**) Lateral turbulence intensities. the increase in wind speed. At 19 m/s < \(U\) < 25 m/s, the turbulence intensity does not change with the increase in mean wind speed, and the mean values of the longitudinal and transverse turbulence intensity are 0.14 and 0.11, respectively. When \(U\) \(\geq\) 25 m/s, the turbulence intensity increases with the mean wind speed, and the along-wind and cross-wind turbulence intensities are 0.19 and 0.15, respectively. In this process, the wind direction angle slowly changes from 55\({}^{\circ}\) to 20\({}^{\circ}\), and the wind speed slowly increases. Meanwhile, the law of building A is completely different from that of building C because a super high-rise building is situated north of building A, imposing an interference effect of the upstream building, which will be considered in the next work through a wind tunnel test. The left side of Figure 8 shows that the turbulence intensity of buildings A and B does not change with the increase in mean wind direction angle, thereby presenting a great dispersion. The turbulence intensity of building C increases with the mean wind direction angle \(\theta\). Between \(\theta\in\) (40\({}^{\circ}\), 45\({}^{\circ}\)), buildings A and C have further intersections at the turbulence intensity sample. The right side of Figure 8 indicates that the turbulence of building A decreases with the increase in mean wind direction angle \(\theta\), and the turbulence intensity remains stable and constant when \(\theta\) > 40\({}^{\circ}\). The turbulence intensity of building C decreases first and then increases with the mean wind direction angle. The inflection point interval is located between the wind direction angles \(\theta\in\) (35\({}^{\circ}\), 45\({}^{\circ}\)).