Understanding the effect of elastic wheels on an urban railway system using a new wheel–rail coupling vibration model

In order to control the wheel–rail coupling vibration of an urban railway system, a combined elastic wheel damping structure is proposed where the key parameters that determine the structural damping and thereby control the vibration of the railway system are explored. The vertical acceleration of the elastic wheels is obtained for a range of stiffness coefficients as the wheel moves on an irregular track, which is calculated by the Newmark - β method in the time domain. The results show that the vertical acceleration changes with a V-shaped trend, with an increase of wheel stiffness coefficient, which allows the optimum stiffness coefficient for minimum vertical acceleration of the elastic wheel to be obtained. It is observed that when attempting to suppress wheel vibration, an elastic wheel with a larger stiffness coefficient is needed as the degree of track irregularity reduces. This paper provides new insights into the effect of wheel elasticity on vibration characteristics, and thereby provides directions to improve ride quality and passenger comfort.