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基于某主跨820m混合梁斜拉桥,利用刚体节段模型风洞试验结合计算流体动力学(CFD)数值模拟,系统研究了半开口分离双箱梁的涡振性能并进行一系列气动控制措施的探讨。该断面成桥状态在+3°或+5°风攻角下会产生大幅竖弯涡振,来流上游侧检修道栏杆处的气流分离起主导作用,检修车轨道对竖弯涡振有放大作用,这主要源于其后方连续产生的小尺度漩涡在断面下部开口内汇聚,形成了能量集中的大尺度漩涡。采用不同形式的检修道栏杆或改变风嘴角度对竖弯涡振控制效果不理想,将风嘴向外延伸可以有效降低振幅,但要保证检修道栏杆不移动,工程实用性较差。下中央稳定板基本没有抑制效果;水平翼板和抑流板都能有效控制竖弯涡振,其中水平翼板可以延缓漩涡能量的集中降低涡振振幅,但不能完全抑制振动,而且大攻角下会延长涡振风速区间;抑流板则直接通过抑制断面上表面漩涡的形成而有效控制涡振发生。
Based on a 820 m hybrid cable-stayed bridge with main span and rigid body segment model wind tunnel test and computational fluid dynamics (CFD) numerical simulation, the vortex-induced vibration performance of a half-opened double box girder is systematically studied and a series of aerodynamic control measures Discussion. The cross-sectioned state of the bridge will generate a large vertical vortices at a wind attack angle of + 3 ° or + 5 °. The airflow separation at the railings on the upstream side of the incoming stream plays a leading role and the overhaul track of the vehicle has an enlarged This is mainly due to the small-scale vortexes successively generated in the rear converging in the lower opening of the section, forming a large-scale eddy with concentrated energy. The use of different forms of inspection railing or change the angle of the nozzle on the vertical Vortex Vibration control is not satisfactory, the nozzle extends outward can effectively reduce the amplitude, but to ensure that inspection railings do not move, the project less practical. Under the central stability plate, there is almost no suppression effect. Both the horizontal flap and the dampening plate can effectively control the vertical bending vortex. The horizontal vane can delay the concentration of the vortex energy and reduce the amplitude of the vortex vibration, but can not completely suppress the vibration. Moreover, Will extend the vortex wind speed interval; inhibition plate directly through the suppression of the formation of the upper surface of the vortex and vortex control effectively.