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不同槽宽分体箱梁可以有效地提高大跨度桥梁的气动稳定性,但是其涡振性能还不够明确,研究了6种代表性开槽率分体箱梁的涡振性能随开槽率的变化规律,对比了4种控制措施(增大阻尼比、可调风障、导流板和隔涡板)的制振效果,并对其进行了综合评价。结果表明:闭口箱梁的涡振性能要优于开槽的分体箱梁;随着开槽率的增大,分体箱梁的竖弯涡振振幅先增后减,扭转涡振振幅表现较为敏感,其中,60%开槽率的竖弯涡振和80%开槽率的扭转涡振振幅最大。对比了60%和20%开槽率分体箱梁,增大结构阻尼比和增设小透风率的隔涡板可以明显的减小不同槽宽分体箱梁的竖弯涡振振幅,增大阻尼比和增设水平风障可以有效地提高不同槽宽分体箱梁的扭转涡振性能,而增设内置、外置导流板对的涡振控制效果取决于开槽率的大小。以上4种控制措施都可以满足分体箱梁的扭转涡振振幅要求,但只有增设0%透风率的隔涡板才能满足Sperling指标和抗风设计规范的竖弯涡振振幅要求。
The box girder with different groove width can effectively improve the aerodynamic stability of the long-span bridge, but its vortex-induced performance is not clear enough. The vortex-vibration performance of six typical slotted split-box girders is studied with the slotting rate Variations of the four kinds of control measures (increasing the damping ratio, adjustable wind barriers, deflector and vortex plate) of the vibration control effect, and carried out a comprehensive evaluation. The results show that the vortex vibration performance of closed box girder is better than that of slotted split box girder. As the slotting rate increases, the amplitude of vertical vortex vibration of split box girder first increases and then decreases, Is more sensitive, among them, the amplitude of torsional vortex vibration of 60% slotted vertical vortex and 80% slotted is the largest. Comparing the 60% and 20% slotted split box girders, the increase of structural damping ratio and the increase of the small ventilation rate of the vortex plate can obviously reduce the amplitude of vertical bending vibration of split box girders with different groove widths and increase The damping ratio and additional horizontal wind barriers can effectively improve the torsional vortex vibration performance of split box girders with different groove widths. The control effect of vortex vibration with built-in and external deflector pairs depends on the slotting rate. The above four kinds of control measures can meet the torsional vortex amplitude requirement of split box girder, but only the vortex plate with 0% ventilation rate can meet the vertical bending vibration amplitude requirement of Sperling index and wind resistance design code.