中信广场风场特性及风致结构振动的同步监测

Simultaneous monitoring of wind characteristic and wind-induced vibration of main tower in CITIC Plaza

通过对广州中信广场在台风“达维”作用下其风场与风致结构振动的现场同步监测,获得了台风风场和结构动力特性,及风致结构振动响应等相关结果。通过对现场测试数据的分析,验证了湍流强度随平均风速增大而减小和阵风因子随湍流强度增大而增大等规律,实测的脉动风速谱与vonKarm an谱亦很吻合。同时通过对中信广场加速度响应与平均风速关系分析得出,该高层建筑物的顶部风速即使处于低中风速范围时,其横风向响应已接近于顺风向响应。根据实测风振加速度数据,对结构动力特性(频率及阻尼比)进行了识别,采用随机减量方法求得了结构在两个主轴方向第一振型阻尼比与振幅的非线性关系。

The simultaneous monitoring of wind characteristics and wind-induced responses of main tower in CITIC Plaza was conducted during Typhoon Damrey. The relationships among turbulence intensity, gust factor and mean wind speed were obtained based on the measured wind speed data at top of the super tall building. Meanwhile, the relationship between RMS acceleration and mean wind speed was established under typhoon condition. Based on the measured acceleration data, amplitude-dependent damping ratios of the building were also obtained by the random decrement method. The typhoon-generated wind characteristics and wind-induced structural vibrations were investigated in detail on the basis of the full-scale measurements.