通过对岳阳洞庭湖大桥拉索风雨振进行了现场实测所获得的拉索振动的加速度时程记录及实时的风场与雨量记录.利用拉索的振动方程与数值计算方法对拉索的振动特征进行了研究.分析结果表明:风雨振是拉索发生的一种大幅、低频振动,拉索风雨振存在一个最低临界风速,并且存在一个风向敏感区.图7,表1,参8.
A preliminary characterization of rain-wind induced vibrations was presented from an ongoing analysis of vibration records obtained from a long-term field measurement program at the Dongting Lake Bridge in Yueyang, Hunan Province,Displacement time history have been generated by least square trigonometric approximation of recorded accelerations and the analysis dynamical equations of stay cables. Preliminary observations of the vibration characteristics and their correlation with wind speed and wind direction presented using the statistics. The results indicate that, rain-wind induced stay-cable vibrations are associated with very large amplitudes and the lower modes,the large-amplitude responses occur over a critical wind speed and the"yaw angle"between 20°and 70°.7figs., ltab., 8refs.