Prediction of vibratory nuisances of rail transport vehicles

Rail vehicles are subjected to more and more severe environmental constraints. The understanding of vehicle-track interaction and ground propagation of vibrations is of increasing interest as well as the prediction of the vibratory nuisances of rail vehicles on the neighbourhood. This paper discusses different prediction models in the context of different vehicle-track-soil systems. Two basic approaches are applied on a urban railway-vehicle and a high speed vehicle. The first one consists of a classical 2D-model for the track with rigid sleepers and discretely supported rails. A flexible rail is modelized by a finite element approach and a ground model using Green's functions is used to compute the propagation of the vibrations at short distance from the source. The vehicle model is formed by the combination of bodies and interconnection elements. In the second approach, each rail is treated as a Euler-Bernoulli elastic beam of uniform mass lying on a viscoelastic half-space. The generated ground vibration is calculed by a function describing the properties of the Rayleigh surface waves generated by the force sleepers. Both models are discussed using experimental results obtained with tramway vehicles (T2000 in Brussels) or high-speed trains (Thalys near Ath).