轨道交通桥梁减振降噪研究进展

随着高速铁路和城市轨道交通的迅猛发展，人们环保意识的增强以及高架线路的广泛应用，轨道交通桥梁振动与噪声已成为亟待解决的问题。首先，介绍了混凝土桥、钢桥、钢混组合桥的典型振动与噪声试验和桥梁结构噪声常用的理论研究方法。其次，从桥梁结构优化的角度，讨论了混凝土桥、钢桥常用的减振降噪措施，并探讨了TMD的减振降噪效果。然后，综述了桥上轨道结构常用的减振降噪措施。最后，总结了3种声屏障降噪效果的研究进展。结果表明：①不同结构桥梁振动与噪声有所差异，总体来说钢结构桥梁振动与噪声问题更为突出；②混凝土梁截面的优化措施具有一定的减振降噪效果，如增设中腹板或横隔板，优化腹板倾角等措施，U梁对轮轨噪声具有遮蔽效应，梁下区域遮蔽损失最大可达10 dB（A），但与传统箱梁相比，U梁结构噪声更大；③约束阻尼结构能够有效控制钢桥振动与噪声，TMD能够有效抑制桥梁结构低频振动，但降噪效果甚微；④在钢轨、扣件、轨枕道床等方面采取相应的减振措施，从而达到轨道交通桥梁减振降噪的目的是最为经济可行的方法；⑤声屏障可有效控制交通噪声，直立声屏障降噪效果为5~10 dB（A），半封闭声屏障降噪效果约15 dB（A），全封闭声屏障降噪效果超过20 dB（A）。

Review on Vibration and Noise Reduction of Rail Transit Bridges

Vibration and noise of rail transit bridges have become an urgent problem with the rapid development of high-speed railways and urban rail transit, the increasing awareness regarding environmental protection, and the extensive application of viaducts. First, several typical vibration and noise tests of concrete, steel, and steel-concrete composite bridges were introduced as well as existing theoretical prediction methods of bridge-borne noise. Second, from the perspective of bridge structure optimization, several commonly used vibration and noise reduction measures for concrete bridges and steel bridges were discussed, and the effectiveness of tuned mass dampers (TMDs) for vibration and noise reduction were demonstrated. Then, the common vibration and noise reduction measures on the track structure were summarized. Finally, the noise reduction effects of three types of noise barriers were compared. The results are as follows: ①The vibration and noise vary with bridge structure, with the steel bridge being the most prominent. ②The optimization of the cross-section of the concrete box girder, such as adding a middle web or diaphragm and changing web angle, can reduce the vibration and noise of a bridge. A U-shaped girder provides a shielding effect on the wheel-rail noise. The shielding loss of the wheel-rail noise under the U-shaped girder can reach 10 dB(A). Compared to the conventional box-shaped girder, the bridge-borne noise of the U-shaped girder is greater. ③A constrained damping structure can effectively control the vibration and noise of a steel bridge. TMDs can effectively suppress the low frequency vibration of a bridge, but the noise reduction effect is slight. ④It is economical and feasible to reduce the vibration and noise of elevated rail transit through track structure design, such as adopting damping techniques on the rail, fastener, sleeper, and ballast. ⑤Noise barriers can effectively control the traffic noise. The noise reduction effect of the straight-type noise barrier is between 5 to 10 dB(A), the noise reduction effect of the semi-enclosed noise barrier is approximately 15 dB(A), and the insertion loss of a fully enclosed noise barrier is higher than 20 dB(A).