Continuous Monitoring of Rail Corrugation Growth Using an In-Service Vehicle

Rail corrugation is a degradation phenomenon that affects almost all the railway lines and for which up to now a definitive solution does not exist. It consists in the appearance of a quasi-periodic irregularity on the running surface of the rail, causing high dynamic loads and, thus, possible failures in vehicle and track components, ground-borne vibrations transmitted to the buildings nearby the infrastructure and acoustic pollution. The only effective treatment to mitigate the rail corrugation problem is the periodic grinding of the rails, performed by dedicated vehicles. A continuous monitoring system for rail corrugation growth has been developed. The roughness profile on the rail running surface is estimated from axle-box acceleration measurements performed by an in-service vehicle. The FRF of the measurement system is calculated from a frequency domain model of the vertical dynamics of the wheel-rail interaction. The estimate of the longitudinal rail profile allows the identification of the track sections where corrugation is present and the monitoring of its evolution. Some differences between estimated and measured peak-to-peak amplitude are present, but the causes have been identified and should be overcome with further experimental tests and refinements of the mathematical model.