大跨度分体箱梁桥梁涡振性能及其控制

Vortex-induced vibration and its control for long-span bridges with twin-box girder

因其相比传统闭口箱梁更为优越的颤振稳定性能,分体箱梁在大跨度桥梁建设中逐渐开始得到应用。以国内已建成的3座采用分体箱梁的大跨度桥梁为背景,通过大尺度节段模型风洞试验对分体箱梁的涡激共振性能进行研究,发现各断面均发生振幅较大的涡激共振。基于粒子图像测速技术的分析表明,在中央开槽处的大尺旋涡很可能是引起大幅度涡振的主要原因。为了解决分体箱梁桥梁的涡激共振问题,尝试和提出包括导流板、隔涡板和可调风障在内的多种气动控制措施,并比选出最佳控制方法。

Vortex-induced vibrations( VIV) performance of twin box girders models for three long-span cable-supported bridges in China is investigated by wind tunnel tests. Vortex-induced vibrations with large amplitude were found on all three different types of twin box girders. Based on Particle Image Velocimetry technique,large scale vortices in the central vent were visualized and considered to have significant influence on the aerodynamic performance of twin box girder,especially vortex-induced vibration. Aerodynamic control measures, including guide vane, grid plate and adjustable wind barrier,are proposed to suppress the self-excited vibration. The three countermeasures are compared and the most optimal one is chosen.