Comparative Analysis On The Vertical Vibration Transfer Characteristics Of Track Structures Commonly Used On The Transit Viaduct

With the rapid development of t the construction of urban rail transit, viaduct is becoming the main form of urban rail lines concerned by the construction and design department because of its less construction invest and maintenance cost. However, the vibration and noise of viaduct radiate into the environment directly, therefore, the control of vibration and noise of urban rail transit viaduct is imperative.It is important to control vibration and noise of the viaduct track structure. On the basis of a lot of the research status of the common track structure vibration of viaduct home and abroad comprehensive summarized in this paper, three-dimensional finite element model of track-bridge was established. This paper mainly studied vertical vibration transmission characteristics of the track structure commonly used on viaduct (vibration damper fastener track, low vibration track, ladder sleeper track and steel spring floating slab track structure) from the perspective of the frequency domain, and vibration characteristics of the system structure that were analyzed and compared under the typical frequency.The research results show that: on different track structure forms, the first resonant frequency is also different, when the harmonic load excitation frequency is lower than the first resonant frequency of bridge, the frequency has a great influence on the vertical vibration deformation of the rail and sleeper (or ballast bed); Overhead line applications The damping track structures of viaduct can be good to reduce the vibration of the bridge, but increase the vibration of the rail and ballast bed in some frequency bands; when the track structure appear anti-resonant, the vertical vibration deformation of the rail and sleeper (or ballast bed) will attenuate by a large amplitude, but the bridge vertical vibration deformation has no attenuation; when the harmonic load excitation frequency is lower than15Hz, different track structure forms have little effect on the vertical displacement of bridge and the bridge bearing transmission force; when the excitation frequency is higher than300Hz, different track structure forms have little effect on the vertical displacement of the rail; in the effective vibration reduction band, the steel spring slab track and the ladder sleeper track have the best effect on vibration reduction. The results this paper analyzed provide a theoretical basis for selection of the damping track structure on bridge and control of vibrations and secondary radiation noise of the viaduct structure.