[Lecture] Mechanism of short pitch rail corrugation: initial excitation and consistent initiation and growth
Speaker: Dr. Shaoguang Li, Eurailscout Inspection & Analysis (ERS), the Netherlands
Time: 15:00, July 15, 2023, GMT+8
Venue:
https://teams.microsoft.com/l/meetup-join/19%3ameeting_MTE3YTYzNmMtZTQ0ZC00YTBjLWFhMTUtMzZhYzUxM2JiNTBi%40thread.v2/0?context=%7b%22Tid%22%3a%220b6b9a6a-d9d6-4ef0-a36f-5dc22f35388b%22%2c%22Oid%22%3a%22b3a4a853-427e-4c6d-b1c2-e9007d3c7aa4%22%7d
Abstract:
Short pitch rail corrugation has been considered as an enigma for more than a century due to its complexity in wavelength-fixing mechanism and the underlying causes. This study proposes a new hypothesis for the formation process of short pitch rail corrugation. An FE wheel-track dynamic model is utilized to verify the hypothesis by reproducing corrugation initiation and consistent growth. It is found longitudinal compression modes are responsible for corrugation initiation with necessary initial excitation that allows flexibility for longitudinal vibration. Consistency between longitudinal compression and vertical bending eigenfrequencies of the wheel-track system is required for consistent corrugation growth, which also determines maximum corrugation amplitude. Corrugation initiates by frequency selection instead of wavelength fixing. The proposed mechanism can explain field observations including the wavelength and periodicity of corrugation in the Netherlands, why corrugation forms on continuously supported tracks where pinned-pinned resonance does not exist, and the small variation between the corrugation wavelength and train speed.
Biography:
Dr. Shaoguang Li received his BSc, MSc, and PhD degrees from Northeastern University and Delft University of Technology. He has been a project manager and R&D engineer at Eurailscout Inspection & Analysis since 2018. His research expertise includes vehicle-track coupled dynamics (transient, thermo-mechanical coupling, and wheel-rail cyclic contacts), railway infrastructure condition inspection, diagnosis, and monitoring.
