Time-frequency characteristics analysis of axle box acceleration in high-speed railway rail corrugation section

Rail corrugation is a common rail disease in high-speed railway. To study the relationship between rail corrugation and the time-frequency characteristics of axle box acceleration, and to explore the feasibility of identifying rail corrugation using axle box acceleration, a rigid-flexible coupled dynamics model was established with the flexible wheelset and axle box. The accuracy of the model was verified by the comparison with the measurements. The VMD-SPWVD method was proposed based on the relationship between rail corrugation and axle box acceleration in time domain. The results show that rail corrugation has a great influence on the axle box acceleration. The maximum positions of axle box acceleration under different wave depths and lengths are random in time domain. There is a certain relationship between rail corrugation and the root mean square. However, as a time domain index, it cannot accurately locate the region of rail corrugation and evaluate its severity. Compared with the time domain method, the VMD-SPWVD can effectively reflect the relationship between rail corrugation and axle box acceleration, and identify the characteristic frequency of rail corrugation without any interference. The energy amplitude increases monotonically with the wave depth. This method can locate the region where rail corrugation exists and reflect its severity at different positions. The effectiveness of this method was further validated by the field test.