Vibro-Acoustic Analysis of the Railway Tracks with Fractional Railpads and Nonlinear Ballast

Noise and vibration from the railway tracks with fractional railpads are studied in this paper. The track system is modeled by a beam on a viscoelastic foundation including the fractional railpads and nonlinear ballast. The nonlinear fractional governing equation is obtained in the time domain by use of the fractional finite element formulation. The Newmark’s method is combined with the Adomian decomposition method (ADM) to solve the nonlinear fractional equation. The acoustical pressure field around the vibrating beam is obtained by the Rayleigh integral approach. The effects of the fractional parameters, load speed and condition on the track responses are investigated. It is found that the dynamic deflection and stress alongside the railways are more influenced by the loading condition, while the acoustical pressure is remarkably influenced by the load speed.