Parameter Influences on Rail Corrugation of Metro Tangential Track

Rail corrugation can reduce riding comfort by vibration and noise, and even cause running accident. In this paper, the vehicle-track coupled dynamic model was developed for a metro's tangential track considering the wear in rail materials. The influences of different track structure parameters and vehicle speed on the generation and development of rail corrugation of the tangential track were analyzed using the developed model by the control variable method. The results show that for different parameters, the friction power in wheel-rail contact patch fluctuates with time, but the overall fluctuation range is relatively uniform. Meantime, an analysis of one-third octave curves of the friction power reveals that the characteristic frequencies of friction power are mainly concentrated in the middle and low frequency bands. At the dominant characteristic frequency, the longitudinal stiffness and damping of fasteners, and lateral and vertical damping of fasteners have less influence on rail corrugation, while the lateral and vertical stiffnesses of fasteners, spacing of fasteners, wheel-rail friction coefficient and vehicle speed have greater effect on rail corrugation. The changes in vertical stiffness and spacing of fasteners will cause the characteristic frequency of friction power to be offset, resulting in a shift from 80Hz to 100Hz, which will further lead to rail corrugation of the corresponding wavelength. Thus, it can be concluded that the vertical stiffness and spacing of fasteners have an important impact on the generation and development of rail corrugation at the specific frequency. Besides, the variations of the other variables bring little change to the characteristic frequencies of friction power as well as on rail corrugation. The mechanism of parameters unveiled here provides some guides for the parameter optimization problem on restraining the generation or development of rail corrugation on the tangential track.

Automated summary

This paper developed a vehicle-track coupled dynamic model and analyzed the influence of different parameters on rail corrugation on tangential track using the control variable method. It was found that the vertical stiffness and spacing of fasteners have a significant impact on the generation and development of rail corrugation at specific frequencies.