超高层建筑风致振动的现场实测与数值模拟

Field Measurement and Numerical Simulation of Wind-induced Vibration of Super High-rise Building

通过采用现场实测和数值模拟方法,对某超高层建筑的风致振动特性进行研究。在建筑物顶部布置结构振动监测系统,对常态风和台风作用下的结构振动响应进行测量,分析加速度、位移幅值和结构的自振特性。以实测动力特性为基础,建立超高层建筑的等效气动弹性模型,采用平均风剖面入口,联合ANSYS和CFX对风场与建筑物的流固耦合振动进行数值模拟,得到不同顶部风速下,建筑物不同高度处的位移时程、气动力系数时程及频谱分析、尾流旋涡脱落模式。将数值模拟结果与现有的实测结果进行对比分析,表明该方法模拟流固耦合振动是可行的,并可为实际超高层建筑的抗风设计和舒适性计算提供技术依据。

The characteristics of the wind-induced vibration of a super high-rise building were studied through field measurement and numerical simulation in this paper. The structural vibra- tion response was measured using structural vibration monitoring systems mounted on the top of the building. The acceleration, displacement amplitude and dynamic characteristics of the struc- ture were analyzed under normal wind and No. 12 typhoon in 2008. Based on the measured dy- namic characteristics, the equivalent aero-elastic model of the super high-rise building was estab- lished. Program ANSYS was used and combined with CFX to simulate the vibration of fluid- structure interaction （FSI） between the wind field and the building. The inlet boundary condition of the mean wind profile was adopted. The time histories of displacement and aerodynamic force coefficient, spectrum analysis and vortex shedding mode at different height and different wind speed on the top of the building are obtained. The top lateral displacement of the building was compared with present and other field measurement results. It is shown that the numerical meth- od adopted to simulate the FSI is feasible and it also can provide necessary technical basis for wind-resistant design and comfort calculations of actual super high-rise building.