Influences of Infrastructure Property on the Train-Track Interaction Due to Track Irregularities

The paper presents a study of the dynamic behavior of a high-speed train-track-bridge system during the train crossing multi-span concrete box girder bridges due to track irregularities. A coupled finite element–multibody dynamics (FE-MBS) model including the train sub-model, the ballastless track sub-model, the wheel-rail contact sub-model and the bridge sub-system are formulated. This model can predict the behavior of the train running on tracks supported by bridge and embankment, as well as the dynamic response of track and bridge structures under train passage. The effects of the wavelengths of track defects on the running quality of train travelling on bridge and embankment are reported. The simulation results show that severe track irregularities such as track vertical profile and alignment defects can arouse the resonance of the vehicle-track-bridge system, and the safety limits for the track defects on bridge should be stricter than that on embankment.