Zheng Weiqi, Sheng Xingwang, Zhu Zhihui, Luo Tianjing, Liu Zecheng
School of Civil Engineering, Central South University, Changsha 410075, China.
National Engineering Laboratory for High Speed Railway Construction, Changsha 410075, China.
Sensors (Basel). 2020 Mar 20;20(6):1744. doi: 10.3390/s20061744.
In this work, we present a series of hammering tests on full-scale unit-plate ballastless tracks used for long-span bridges. There is no denying that it is a new attempt to pave ballastless tracks on high-speed railway long-span bridges; the related issues deserve to be studied, and especially the vibration characteristics. Hence, the vibration characteristics and transmission rules of the ballastless track with geotextile or rubber isolation layers are explored, and the vibration reduction effect of the rubber isolation layer is analyzed. The main conclusions are as follows: the isolation layers change vibration modes and transmission characteristics of ballastless tracks; the introduction of the rubber isolation layer makes the excited vibration frequency range of the ballastless track concentrated; and the vibrations of the ballastless track with the rubber isolation layers are stable. Moreover, the rubber isolation layer has an obvious attenuation effect on vibration transmission in ballastless track structures. When the vibration is transmitted from the rail to the bridge deck, the vibration level differences of the ballastless track with rubber isolation layers are 20 dB larger than that of the ballastless track with the geotextile isolation layers. The vibration attenuation rate of the rubber isolation layer is about ten times larger than that of geotextile isolation layer.
在这项工作中,我们对用于大跨度桥梁的全尺寸单元板式无砟轨道进行了一系列锤击试验。不可否认,在高速铁路大跨度桥梁上铺设无砟轨道是一项新的尝试;相关问题值得研究,尤其是振动特性。因此,探索了带有土工织物或橡胶隔振层的无砟轨道的振动特性和传播规律,并分析了橡胶隔振层的减振效果。主要结论如下:隔振层改变了无砟轨道的振动模式和传播特性;橡胶隔振层的引入使无砟轨道的激振频率范围集中;带有橡胶隔振层的无砟轨道振动稳定。此外,橡胶隔振层对无砟轨道结构中的振动传播具有明显的衰减作用。当振动从轨道传递到桥面板时,带有橡胶隔振层的无砟轨道的振动级差比带有土工织物隔振层的无砟轨道大20 dB。橡胶隔振层的振动衰减率约为土工织物隔振层的十倍。