The influences of rail vibration absorber on normal wheel-rail contact forces due to multiple wheels

A compound track-absorber model with multiple wheels on the rail is employed to study the effects of a rail absorber on the normal wheel-rail contact forces in the frequency domain. Two different absorber models, which are the piecewise continuous absorber and the discrete absorber installed in the middle of the sleeper span, are presented. It can be seen from the calculation results that there are more peaks occurring in the frequency range of 500-1200 Hz due to the wave reflections between the wheels than that of a single wheel-rail interaction. However, these peaks are all suppressed due to the effects of the rail absorber, and there are new peaks appearing at other frequencies while the amplitude of these peaks is relatively small. The peaks in contact force at low frequencies are higher, whereas the peak at pinned-pinned resonance is suppressed.