稳态冲击风作用下高层建筑风荷载特性试验研究

雷暴冲击风风场与大气边界层风场差异较大.为研究雷暴冲击风作用下高层建筑风荷载特性,采用静止型冲击射流装置模拟稳态雷暴冲击风风场,进行高层建筑刚性模型测压试验,讨论了不同径向位置处高层建筑局部和整体风荷载时域和频域特性.结果表明:建筑表面平均风压最大值出现的位置与径向风速峰值一致.同时,迎风面风压最大值出现在底部,明显不同于大气边界层风场中最大值靠近顶部位置的风压分布特性;径向层风荷载均值最大值出现在建筑中部,横风向和扭转向层风荷载均值为0.径向和横风向层风荷载谱沿高度不变,而扭转向层风荷载谱沿高度变化明显.

Experimental Study on the Wind Load Characteristics of High-rise Building in Stationary Downbursts

Downbursts are dramatically different from the atmospheric boundary layer. To investigate the wind load characteristics of high-rise building in thunderstorm downbursts, a static impinging jet was used to simulate the thunderstorm downburst. Rigid model manomeric test was carried on a high-rise building. Both local and overall wind load characteristics were discussed in time domain and frequency domain. The results indicate that the position of the maximum mean surface pressure is consistent with the peak radial velocity. Meanwhile, the maximum surface pressure on the windward side is located at the bottom of the building, obviously different from the top part tested in atmospheric boundary layer wind field. The maximum mean radial wind load of each layer is located at the middle of the building. And the mean wind load is 0 at the cross-wind and torsional direction. Wind load spectrums of each layer keep unchanged along the height at the radial and cross-wind direction. But wind load spectrums changes obviously at the twist direction.