山区桥梁桥址风环境试验研究

北盘江特大桥位于地形特殊的山区．通过模拟桥址地形的风洞试验，确定桥梁设计基准风速和相关的风特性参数，使得到的风速真正反映桥址处风的实际状况．试验结果表明：北盘江特大桥桥址处无明显风速放大效应；根据荷载等效原则，桥面设计基准高度可采用统一的等效桥面高度来描述；当横桥向来流，且与山谷走向一致时，桥面高处的水平方向和竖向脉动风功率谱密度在脉动风的振动频率的低频区域，可以分别近似采用Kaimal谱和Panofsky谱，

Experimental Study of Wind Field in Bridge Site Located in Mountainous Area

The ultra long span bridge of Beipan river across the V shape valley is located in a complex terrain. The design reference wind speed and related wind characteristic parameters of the bridge are derived from the wind tunnel test of a terrain model of the bridge site. Results show that the bridge site has no notable magnification effect of wind speed. According to the equivalent load principle, the design reference height on the bridge deck can be described with the equivalent height of bridge deck. The power spectra density of horizontal component and vertical component of fluctuation wind on the bridge deck respectively can be approximately expressed as the spectra of Kaimal and the spectra of Panofsky in low-frequency range of long span bridge under the coming wind from acro-bridge directions parallel to the trend of the valley.