Severity and growth evaluation of rail corrugations on sharp curves using wheel/rail interaction

A railway network generally spans over a large distance so the structural health monitoring of such a rail infrastructure system is one of the critical challenges in rail industry practice. Especially in an underground/subway or elevated system, the facilities, resources and time period permitted for critical infrastructure inspection and maintenance is considerably limited. As a result, the automated inspection system of railway is in very high demand. Rail corrugation defect is the periodic, undulated or wave-like vertical alignment of rail surface. The wavelength and severity of rail corrugations is dependant to track structure, track geometry, traction system, rail vehicle behaviours, and wheel-rail interaction. The rail corrugations are the source of rapid track degradation, poor ride comfort, and nuisance noise. Often such rail irregularities are observed on the low rail of small-radius or very sharp curves. This paper presents the utilization of an inspection train vehicle to evaluate and monitor rail corrugation growth on sharp curved tracks. As a case study, a set of rail surface data of a very sharp curve was chosen for demonstration. This study shows the severity and growth evaluation of rail corrugation by integrating numerical train/track simulations, axle box acceleration data obtained from the calibrated track inspection vehicle “AK Car”, and spectral data analytics.