The dynamic behaviour of rail fasteners at high frequencies

The stiffness and damping of rail fasteners, and in particular the elastomeric pads inserted between the rail and sleeper, are important parameters determining the dynamic behaviour of railway track. For noise predictions, the frequency range from about 100 Hz up to 5000 Hz is important. Laboratory measurements are described in which the vertical and lateral dynamic stiffnesses of rail fastener systems have been measured under preload in the range 100–1000 Hz. Extension of the method to higher frequencies is also possible but would require a modified test arrangement. Field measurements are also described, which allow the stiffness and damping to be derived indirectly. Comparisons are made between the two sets of data