VIBRATION ANALYSIS OF TRACK-EMBANKMENT ON RIGIDFOUNDATION BY USING 2.5D FINITE ELEMENT METHOD

A two-and half dimensional (2.5D) finite element (FE) model of the track-embankment system on rigid foundation has been firstly established for analyzing the track vibration due to moving harmonic load, and then the vehicle-track-embankment system model is also proposed. This model allows arbitrarily shaped cross section of the track-embankment system only if the system can be assumed as homogeneous along the track direction. The 2.5D FE model is verified by comparing with the results from the existing analytical model. The traditional multi-beam model of the track-embankment system in the field of vehicle-track coupled dynamics can be substituted easily by the current model. Influences of height of embankment on vibration characters of the track-embankment system are analyzed and some useful conclusions are gained. The dynamic wheel rail forces due to track irregularities within the frequency range are calculated. Comparing with the conventional 3D FE model, the computation efficiency of the 2.5D FE model is very higher.