In order to provide reliable basis for wind resistant evaluation of a long-span suspension bridge,the wind field monitoring system was installed and the simultaneous wind data at the bridge deck and the top of bridge tower were recorded.The variation of wind speeds with height,turbulent intensity,gust factor and turbulent wind spectra were analyzed by using statistical methods and spectral analysis.The results show that the dimensionless exponent is unstable at low wind speed and it decreases with the increase of the average wind speed.The mean statistical result is 0.161 at high wind speed,which is higher than the recommended value.The measured turbulence intensity also decreases with the increase of average wind speed,and it can be well fitted by exponential function.The mean statistical results of along-wind,cross-wind and vertical directions are 0.180 6,0.156 4 and 0.078 7,respectively,which are also greater than the recommended values.The gust factors have an approximately linear relationship with the turbulence intensities.The turbulence power spectrum can well fit the standard spectrum.However,the measured spectral values are considerably smaller in low frequency ranges.%为了对大桥抗风评估提供可靠依据,结合东海某大跨度悬索桥的风场监测系统,对该桥桥面及桥塔处的风速进行长期监测,采用统计方法及频谱分析对桥位处风速随高度变化、湍流强度、阵风因子以及脉动风的功率谱密度等进行分析.研究结果表明:无量纲幂指数在低风速时较不稳定,随风速增大而减小并趋于平稳,高风速下其统计均值为0.161,大于规范建议值；湍流强度亦随风速增大而减小并趋于平稳,可采用指数函数加以拟合,桥面高度处强风的顺风向、横风向及竖向湍流强度均值分别为0.180 6,0.156 4及0.078 7,亦大于规范建议值；阵风因子与湍流强度之间近似呈线性关系；强风的水平及竖向风谱与规范谱吻合较好,但实测谱值在低频段偏低.
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