ABSTRACT
The dynamic behaviour of track plays an important role in the generation of wheel-rail rolling noise. Vibrations generated at the contact zone, are transmitted through the track and wheel structures, and these vibrations are then responsible for radiating air-borne noise. The track dynamic behaviour influences this process through the wheel-rail interaction and also through the transmission of vibrations along the track. Three alternative theoretical models of the dynamic behaviour of railway track in the frequency range 50–6000 Hz are described. Using these models various physical phenomena of importance to rolling noise generation are pointed out, and the advantages and short-comings of the three models are compared. Finally, laboratory measurements are described in which the vertical and lateral dynamic stiffnesses of rail fastener systems has been measured under preload in the range 100–1000 Hz. The chapter highlights the three track models using results for a single track type and various physical phenomena.
