Formation mechanism of rail corrugation on the small radius curve of metro based on stick-slip torsional vibration

In order to clarify the formation mechanism of rail corrugation on the small radius curve of metro, the dominant characteristic wavelength of corrugation was obtained based on the measured data. Then, by using the vehicle-track rigid-flexible coupling model and the multi-wheelset-track three-dimensional finite element model, the relationship between wheel-rail stick-slip torsional vibration characteristics and corrugation, when the vehicle/wheelset passed through the curve line, was analyzed, and the cause of corrugation was explained. Finally, the formation mechanism of wheel-rail stick-slip torsional vibration was further explored. The field investigation shows that the inner rail has serious corrugation on the top surface, and the dominant characteristic wavelength of corrugation is 40 mm; side corrugation exists on the outer rail, and it is relatively slight on the whole. The numerical results illustrate that the inner wheel-inner rail lateral stick-slip torsional vibration of the guiding wheelset promotes the formation of the inner rail corrugation; the outer wheel-outer rail of the trailed wheelset also has the occurrence possibility of lateral stick-slip torsional vibration, but the intensity is weak and the probability is low. The state of superelevation affects the formation mechanism of wheel-rail stick-slip negative slope of curve tracks, which determines the occurrence probability of corrugation. Therefore, appropriately increasing the track superelevation can effectively reduce the inner rail corrugation on the small radius curve. © 2022 Southeast University. All rights reserved.