为给复杂地形下的桥梁抗风设计提供指导，以肇庆南广铁路西江大桥为工程背景，依托大桥风环境监测子系统，对桥位处风场进行了现场实测，并以该实测数据为分析样本，从平均风与脉动风两方面研究了其风场特性，同时针对大桥不同测点风速展开了空间相关性分析。实测结果表明：受地形影响，桥位处10 min平均风速呈非高斯分布，湍流强度、阵风因子随高度增加呈增大趋势；湍流强度、积分尺度均大于规范推荐值，纵向脉动风功率谱在高频段与Kaimal谱吻合较好，而在低频段相差较大，跨中与拱顶实测相关系数与Davenport公式计算值均存在一定偏差；基于此类地形下的桥梁设计需考虑地形的影响。%To provide reference for wind‐resistance design of bridges in challenging topogra‐phy ,the Xijiang River bridge on Nanning‐Guangzhou High‐speed Railway in zhaoqing was taken as the engineering background .The wind field at the bridge site was measured by the wind environ‐ment monitoring subsystem .The measured data were used as specimens based on which the char‐acteristics of the wind field were studied from aspects of average winds and fluctuating winds .In light of wind speeds at different measuring locations ,spatial correlation analysis was carried out . The results of the measurement indicate that the 10 min average wind speed at the bridge site fol‐lows non‐Gaussian distribution due to the influence of topography ,and the strength of torrents and gust factors tend to be bigger as the increase of height .The turbulence strength and integral scale are greater than the recommended values in the codes .The high‐frequency spectrum of the longitu‐dinal fluctuating wind is in good agreement with the Kaimal spectrum ,but the low‐frequency spec‐trum with great difference .the measured correlated factors at the midspan and the arch crown are not in good compliance with the values gained by Davenport formula .Thus ,it is proved that the design of bridges in such environment should take into account the influence of topography .
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