对高度600m的超高层建筑——深圳平安金融中心在外界环境风激励下的风振响应进行了现场实测。通过安装在塔楼118层的2组加速度传感器测得结构的风致加速度响应,采用经验模态分解法(EMD)与随机减量技术(RDT)相结合的方法计算了结构的自振频率和阻尼比。建立了深圳平安金融中心三维有限元模型,通过有限元分析得出结构的自振频率,并与实测结果进行对比。结果表明:由EMD和RDT相结合的方法计算得出结构1阶横弯自振频率约为0.12Hz,阻尼比为0.3%-0.6%;结构1阶扭转自振频率约为0.28Hz,阻尼比为0.8%-1.0%;深圳平安金融中心实测结构自振频率和阻尼比与其他结构高度相似的超高层建筑实测结果相近,且实测结果和有限元分析结果吻合较好,验证了EMD和RDT结合方法分析超高层建筑模态参数的有效性;测试结果可以为超高层建筑设计和相关研究提供依据。
The 600 m height super high-rise building of Ping'an Financial Center (PAFC) in Shenzhen was field measured under external ambient wind excitation. The wind-induced acceleration responses of the structure were measured by the two groups of acceleration sensors installed on the 118th floor. The natural frequency and damping ratio of the structure were calculated by combining empirical mode decomposition (EMD) and random decrement technique (RDT). The three-dimensional finite element model of Ping'an Financial Center in Shenzhen was established, and the natural frequency of the structure was obtained by finite element analysis. The results show that using EMD and RDT combination method, the first-order transverse natural vibration frequency is about 0.12 Hz, the damping ratio is 0.3%-0.6%; the first-order torsional natural vibration frequency is about 0.28 Hz, the damping ratio is 0.8%-1.0%. The measuring natural vibration frequency and damping ratio of Ping'an Financial Center in Shenzhen are close to other similar high-rise structures, and the measured results are in good agreement with the finite element analysis results, which verifies the effectiveness of EMD and RDT combination method to analyze high-rise building modal parameters. The measured results can provide the basis for the design of super high-rise building and related research.