Abstract It is essential in a bridge design to study the wind parameters at the bridge site, particularly in a complex mountain area where the wind characteristics vary from location to location. The aim of this paper is to study the wind characteristics in a Y-shaped valley in mountainous terrain, the site of a proposed long-span bridge. Data recorded continuously for almost two years by a Doppler Sodar observation system installed at the bridge site was analysed. The results show that the terrain-induced effect plays a significant role in the wind direction variation and there are regular changes in characteristics depending on the direction. To supplement the full-scale measurements, wind tunnel tests were also carried out using a high-precision terrain model at a scale of 1:1500. Vertical profiles of velocity and turbulence at key points along the bridge, and the lateral profile along the bridge axis were studied. The results from the different test directions showed the influence of the incoming flow field particularly shielding and channelling effects which contribute to wind deceleration and acceleration at the bridge location respectively. Furthermore, the speed-up of the valley and mountaintop is evident and there is greater acceleration at the mountaintop.

中文翻译：

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Y型河谷桥位风特性现场实测及风洞研究

摘要 在桥梁设计中，研究桥梁场地的风参数是必不可少的，特别是在风特性因位置而异的复杂山区。本文的目的是研究山地地形中 Y 形山谷的风特性，该山谷是拟建的大跨度桥梁的所在地。对安装在桥位的多普勒声雷达观测系统连续记录了近两年的数据进行了分析。结果表明，地形诱导效应对风向变化有显着影响，特征随风向变化有规律性。为了补充全尺寸测量，还使用高精度地形模型以 1:1500 的比例进行风洞试验。研究了桥梁关键点处速度和湍流的垂直剖面，以及沿桥梁轴线的横向剖面。不同测试方向的结果显示了传入流场的影响，特别是屏蔽和沟道效应，分别有助于桥梁位置的风减速和加速。此外，山谷和山顶的加速很明显，山顶有更大的加速度。