广州西塔风致响应和气动阻尼特性的试验研究

An experimental study on the wind induced response and aerodynamic damping of Guangzhou West Tower

在边界层风洞中对432m高的广州珠江新城西塔进行多自由度气动弹性模型试验,并和刚性模型的高频底座力天平(HFBB)结果作比较,采用随机减量技术(RDT)识别该超高层建筑的气动阻尼特性。结果显示:在采用相同的阻尼比情况下,气弹模型和HFBB的结果具有较好的一致性;西塔的横风向气动阻尼基本上均为正数,在低风速段随风速的增加而增加,在梯度风风速为45.4m/s时达到最大值为1.75%,随后在临界风速附近急剧下降,在51m/s时降到最小值,约为-0.06%。得出的一些结果可以作为西塔抗风设计参考的依据。

An experiment study of the Guangzhou West Tower （GWT） with a height of 432 meters is carried out by using the MDOF aero-elastic model technique in a boundary layer wind tunnel at Shantou University, and the results are compared with those of the stiffness model based experiment using the high frequency base balance （HFBB） technique. The Random Decrement Technology （RDT） is applied to identify the aerodynamic damping of GWT. Good agreement in wind-induced response is found between the two techniques when same damping ratio is employed to calculate the wind induced response in the HFBB approach. Generally, the aerodynamic damping of GWT is positive for a large range of wind speed. The results show that the aerodynamic damping increases with the increase of the wind speed and a maximum aerodynamic damping of 1.74% is found when the wind speed at the gradient wind height is 45.4m/s. The aerodynamic damping decreases rapidly near the critical wind speed and a minimum aerodynamic damping of -0.06% is found at a wind speed of 51m/s. Conclusions are summarized to serve as a reference for the wind-resistant design of GWT.