Abstract: A study on the vibration reduction characteristics of damping wheel operating on the straight section is carried out using linear motors vehicles under normal and bad wheel/rail conditions through field experiment and numerical simulation. The field test obtains the vibration characteristics of the track components and the tunnel wall under the normal conditions. The test results show that the damping wheel has a good suppression effect on the vibration of the track infrastructure, and its damping effect can reach up to 2-3 dB vibration reduction. The damping wheel also has a good vibration damping effect on the wheel polygonal impact vibration.Since then, in order to further explore the vibration reduction effect of the damping wheel in the extreme conditions(geometric defects of welded rail joint and rail corrugation), a vehicle-track coupling dynamics model is established to numerically simulate the vibration characteristics of the track parts and the tunnel wall when the train with the damping wheels passes through the rails with the welded joint geometry and the corrugation. In the model, the damping wheels is considered to be composed of three parts: wheel core, left rim and right rim, each of which is taken into account 6 degrees of freedom, and the core and rim are connected by using pressing rubber layer. The simulation results show that the damping wheel has a better vibration reduction effect on the rail in the situation of serious geometric defects at rail welded joint and serious rail corrugation, and its damping effect can reach up to 4-7 dB. in which the higher the running speed, the more obvious the vibration reduction effect is.

Key words: straight metro track, damping wheel, dynamic characteristics, field test, vibration reduction