Based on the theory of vehicle-track coupling dynamics, a model of vehicle-track coupling
vibration is established, in which a rail is assumed to be a Timoshenko beam resting on the discrete
sleepers. The natural vibrations of tracks are analyzed, and dynamic responses between vehicle and
track caused by track irregularity are also preliminarily investigated. The characteristics of the
natural vibration and forced vibration of the Timoshenko beam model are different from those of
Bernoulli-Euler beam model. It is shown that the Timoshenko beam model is more applicable to
describing the high-frequency vibration of rails.