Evaluating the degradation of ballasted track at bridges for high-speed railways

The bridge design for railway bridges is far more dependent on the interaction with the traffic and the carriageway than for road bridges. This is especially true for the specific demands of the track in high-speed railways. Both maintenance and safety of the track have to be considered. The most relevant sections for the design criteria can be located at the bridge transition zones. Based on experimental investigations it is shown that bridge joint displacements, changes in stiffness and uplifting of the sleeper are causes for an increased degradation and loss in strength of the ballasted track. With respect to high speed vibrations of the bridge deck can have an even more decisive impact. Bridge deck vibrations can lead to destabilization of the ballast. In a numerical study the behavior of the track at the bridge is illustrated.