铁路简支箱梁阻尼板材减振性能模型试验研究

Model Test Study of Damping Performance of Damping Plate of Railway Simply-Supported Box Girder

为研究阻尼板材对铁路简支箱梁桥的减振效果,以某铁路桥32m简支箱梁为原型,制作几何缩尺比10∶1的简支箱梁相似模型,分别在模型梁跨中截面腹板、翼板、底板敷设阻尼板材,对模型梁进行锤击试验,测量各部位的振动响应,研究阻尼板材对腹板、翼板、底板的减振效果。结果表明:箱梁翼板振动随频率增加缓慢衰减,腹板和底板的振动在中高频段衰减较快;振动由顶板传递至底板时衰减最快,传递至翼板时衰减最慢;在腹板敷设阻尼板材后,腹板的振动显著减小,底板的振动有一定程度减小,翼板的振动变化很小;在翼板、底板敷设阻尼板材后,相应部位的振动均大幅减小;阻尼板材能大幅降低箱梁各板件的振动,具有良好的减振效果。

To study the damping effect of the damping plate to the simply supported box girder of the railway bridge, the similar model of the simply supported girder was made on a geometric scale of 10 ： 1 by selecting a simply-supported girder with span of 32 m of a railway bridge as the prototype. The damping plates were laid on the webs, wing plates and bottom plates of the middle section at the mid span of the model girder to carry out the hammer tests respectively, and the vi bration responses of various parties of the model girder were measured to study the damping effecct of the damping plate to the webs, wing plates and bottom plates. The results show that the vibra tion of the wing plates of the box girder decrease slowly with the increase of the frequency, and the attenuation of the vibration of the webs and bottom plates is fast in the middle and high frequency range. The attenuation of the vibration transmitting from the top plates to the bottom plates is the fastest, while the attenuation of the vibration transmitting from the top plates to the wing plates is the slowest. After the damping plates were laid on the webs, the vibration of the webs decreases obviously, the vibration of the bottom plates decreases to a certain extent, and the vibration of the wing plates has very little changes. With the damping plates being laid on the wing plates or the bottom plates, the vibration of the corresponding parties decrease significantly. The damping plates can greatly decrease the vibration of each plate on the box girder and have good damping effect.