Prognosis of railway ballast degradation for turnouts using track-side accelerations

Maintenance of railway turnouts is a major cost driver for any infrastructure manager, which performs it based on preventive or periodic policies to guarantee minimum downtime of the infrastructure. Ballast maintenance activities, such as tamping, are scheduled by thresholding indicators derived from track geometry data in agreement with European standards. Current industrial practice adopts the same procedures for the evaluation of track geometry degradation in open track and turnouts. This lack of specificity may determine unnecessary maintenance actions with detrimental effects to the turnout dynamical performance. By employing track-side measurements of track acceleration, a probabilistic method for turnout’s ballast quality monitoring was derived by Barkhordari et al. The paper further develops such monitoring system by establishing a mapping between its output and the standard indicator of track geometry quality used by infrastructure managers to schedule ballast maintenance. This results in a predictor of track geometry quality with variable prediction horizon that is functional to the railway infrastructure manager for the predictive planning of ballast maintenance.