Influence of track status on vehicle onboard measurements

Abstract

This study sets out to explore a possible correlation between track quality and data collected by onboard measurement systems. With the rise of condition-based maintenance on railway vehicles, onboard measurement systems could be exploited to assess track quality in addition to their original purpose. An SJ X40 train operating revenue traffic creates the foundation for this study. Onboard measurement data from 2022 have been examined together with track measurements to form a basis for a correlation analysis. Axle strain measurement have been converted into stress spectra which have been analysed using a truncated normal distribution. This in turn was related to track quality data corresponding to the time periods from when the onboard measurements were taken. A possible correlation was explored through linear regression and Pearson’s correlation coefficient. The resulting analysis could not establish a correlation between track quality and onboard measurements, however some results indicate that a correlation might exist. Through the same analysis, it was possible to conclude that the influence of track characteristics dominate over track quality in the onboard measurement data, showing the need to filter the onboard measurements when making assessments of track quality.