A DOUBLE TIMOSHENKO BEAM MODEL FOR VERTICAL VIBRATION ANALYSIS OF RAILWAY TRACK AT HIGH FREQUENCIES

Models of track vibration representing the rail as a beam are insufficiently detailed for high frequencies where the rail cross-sectional deformation is significant. A double Timoshenko beam model is developed for vertical vibration analysis at high frequencies. Although simple, this model includes the essential cross-sectional deformation of a rail in vertical vibration at high frequencies. Based on this model, the dispersion relation of propagating waves in a free and a continuously supported rail is studied. Vertical vibration receptances of the rail are calculated using both continuously and discretely supported models. The results show good agreement with an FE model and measurement data in terms of frequency-wavenumber curves, point receptance and vibration decay rate.