风攻角对斜拉桥抖振的影响

Influence of the Wind Attack Angle on the Cable-stayed Bridge Buffeting

在桥梁所处的自然环境中,来流风是有一定攻角的,在对桥梁进行抖振分析时,有必要对桥梁在不同攻角脉动风作用下进行分析计算,得出不同攻角下桥梁的抖振响应。文中以某公铁两用斜拉桥为例,采用谐波合成法模拟了该桥在基准风速下的脉动风场,采用线性时域分析方法研究了风攻角对斜拉桥抖振的影响。结果表明,该桥的抖振位移响应在正攻角下偏于不利。

The natural wind usually flows around bridges in operation with some attack angle. During the buffeting analysis of o bridge, it is necessary to take the wind attack angle into account to obtain the buffeting response. In the present paper, based on a highway-railway cable-stayed bridge, firstly the fluctuating wind field under design standard wind speed is generated by harmonic wave superimposing method, and then the influence of attack angle is researched by using linear structural dynamics method in time domain. The result shows that the positive attack angle has an adverse impact on the buffeting response of the bridge.