Track Effects on the Dynamic Behavior of a Railway Bridge

초록

The dynamic behavior of the railway bridge begins from the relationship between the dynamic properties of the bridge and the vibration characteristics of the moving train. A precise application of the dynamic properties of a structure will lead to a precise description of the dynamic behavior of a structure under moving train. A track can change modal properties of the railway bridge, through the contribution of stiffness as well as mass. Consequently, the critical speed of the train that gives rise to the resonance behavior should be also changed, with or without the track. In the present study, a steel composite bridge was fabricated, and modal testing was carried out with the installation of non-ballast, ballast track and concrete track. Natural frequencies, damping ratios and responses were observed, along with variation of magnitudes, frequencies and amplitudes of loading. From the results, the effects of a track can be evaluated.