Influence Analysis of Irregularities on Vehicle Dynamic Response on Curved Track of Speed-Up Railway

Track irregularity is the main cause of railway vehicle vibration and wheel-rail dynamic interactions. In this paper, a set of irregularity data on curved track of speed-up railway was taken as examples to analyze the influences of track irregularities on vehicle dynamic response. The data of track irregularities, car-body acceleration and wheel-rail forces was collected from track inspection car with vehicle speed of 180 km/h. Ordinary coherence analysis between Irregularity and dynamic response is conducted in order to determine detrimental wavelength ranges of track irregularity. Partial coherence is conducted for irregularities that have great impact on dynamic response with removing other irregularities. Results of analysis present that car-body vertical acceleration is controlled by vertical profile irregularity on wavelength of 4m∼100m, while car-body lateral acceleration is mainly determined by cross-level irregularity on wavelength of 6m∼10m when signal of alignment irregularity is removed, but wheel-rail forces are weekly coherent with medium- and long-wave irregularities. In addition, the detrimental wavelength ranges become narrow as the radius of the curved track gets small.