The Research Of The Vibration Properties And Isolation Effects Of Rubber Pad Floating Slab Track

With the development of the urban transit system, more and more concerns are placed on the vibration isolation technology of rail transit structures. The slab track with rubber vibration isolation bearing as a new type of track vibration reduction products has been widely used in the national railway and urban rail transit construction in recent years.In this paper, on the basis of original studies, the theoretical simulation analysis of the slab track with rubber vibration isolation bearing was made to discuss how the changes in each structural parameter of the track influence the track’s dynamic property, its insertion loss and the vibration isolation effect of the slab track, especially in tunnel how those changes affect the ground surface vibration and the insertion loss, which can further contribute to the localization of the slab track with rubber vibration isolation bearing.The concrete work is as follows:A3D finite element model of the slab track with rubber vibration isolation bearing was built. The vibration transferring property of the track was analyzed based on the vibration transmission property analysis principle to search into the dynamic responses and the vibration isolation effect of the slab track with different parameters. Also with a3D finite element model of tract-tunnel-soil system constructed, based on the resonance analysis principle of track structure, the transmission characteristics were analyzed and the changes in dynamic response and insertion loss under the influence of the track structure in different parameters was also discussed.This paper mainly achieved as follows:First, vibration isolation bearing can effectively decrease the vibration, greater than the first formant frequency, passing to the sub-structure, while it intensify the vibration response of the rail and the track slab,too, which especially increases the admittance values of the rail and slab within low frequency band. In practice, by each parameter adjustment, the attempt of reducing system vibration as far as possible and improving vibration reduction frequency range of the slab track system, the improving vibration isolation effect was gained.Second, for the ground surface vibration transmitted from the slab track with rubber vibration isolation bearing in tunnel, since the bearing vibration intensifies the rail and slab’s vibration reponse, the noises in tunnel will mounts.Third, since fastener stiffness imposes a slight impact on the vibration under200Hz passing to the ground, it can’t be a dominant factor in choosing the whole track system.Although the slab track with rubber vibration isolation bearing, this study results also provides some reference value for other mass-spring vibration isolation track systems.