菱形双塔楼高层建筑气动力谱研究

Research on aerodynamic spectra of diamond-shaped twin-tower tall building

通过刚性模型同步测压风洞试验得到菱形双塔楼高层建筑各风攻角下顺风向及横风向激励,对其进行谱变换及归一化得到塔楼各测点层无因次气动力谱曲线。以各学者提出的层风荷载功率谱数学模型为基础采用最小二乘法对试验数据进行拟合,分析得出双塔楼对流场的相互扰动使得塔楼在不同风攻角下的气动力谱发生显著变化;同时将拟合得到的顺风向气动力谱与基于风速功率谱推导的结果进行比较得出,受尾流干扰部分风攻角下两者差异较大;对横风向气动力谱构成成分进行分析得出,两塔楼均存在部分风攻角尾流涡脱落形成受抑制的情况,使得横风向气动力谱谱峰不明显,带宽较大。

The along-wind and cross-wind excitations of diamond-shaped twin-tower tall building at different wind angles of attack were obtained by synchronous pressure measurement wind tunnel tests of rigid models.The dimensionless aerodynamic spectrum curves of each measuring point layer of the tower were obtained by spectral transformation and reduction.Based on the mathematical model of layer wind load power spectrum proposed by various scholars,the least square method was used to fit the experimental data.It is concluded that the mutual disturbance of the two towers to the flow field makes the aerodynamic spectrum of the towers change remarkably at different wind attack angles.At the same time,the fitting aerodynamic spectrum along the wind direction is compared with the results derived from the wind speed power spectrum to conclude that the two towers are disturbed by wake flow.There is a big difference between them under partial wind attack angle.By analyzing the components of cross-wind aerodynamic spectrum,it is concluded that the wake vortex shedding at partial wind attack angle is restrained in both towers,which makes the peak of cross-wind aerodynamic spectrum not obvious and the bandwidth wider.