Yan Lei, Ren Lei, He Xuhui, Lu Siying, Guo Hui, Wu Teng
School of Civil Engineering, Central South University, Changsha 410075, China.
Railway Engineering Research Institute, China Academy of Railway Sciences, Beijing 100081, China.
Sensors (Basel). 2020 Feb 24;20(4):1228. doi: 10.3390/s20041228.
This study carries out a detailed full-scale investigation on the strong wind characteristics at a cable-stayed bridge site and associated buffeting response of the bridge structure during construction, using a field monitoring system. It is found that the wind turbulence parameters during the typhoon and monsoon conditions share a considerable amount of similarity, and they can be described as the input turbulence parameters for the current wind-induced vibration theory. While the longitudinal turbulence integral scales are consistent with those in regional structural codes, the turbulence intensities and gust factors are less than the recommended values. The wind spectra obtained via the field measurements can be well approximated by the von Karman spectra. For the buffeting response of the bridge under strong winds, its vertical acceleration responses at the extreme single-cantilever state are significantly larger than those in the horizontal direction and the increasing tendencies with mean wind velocities are also different from each other. The identified frequencies of the bridge are utilized to validate its finite element model (FEM), and these field-measurement acceleration results are compared with those from the FEM-based numerical buffeting analysis with measured turbulence parameters.
本研究利用现场监测系统，对某斜拉桥桥址处的强风特性以及桥梁结构在施工期间的相关抖振响应进行了详细的全尺度调查。研究发现，台风和季风条件下的风湍流参数具有相当程度的相似性，可将其描述为当前风致振动理论的输入湍流参数。纵向湍流积分尺度与区域结构规范中的一致，但湍流强度和阵风因子小于推荐值。通过现场测量获得的风谱可用冯·卡门谱很好地近似。对于桥梁在强风作用下的抖振响应，其在极端单悬臂状态下的竖向加速度响应明显大于水平方向的响应，且随平均风速的增长趋势也互不相同。利用识别出的桥梁频率对其有限元模型进行验证，并将这些现场测量的加速度结果与基于有限元模型且采用实测湍流参数的数值抖振分析结果进行比较。
