Dynamical Behavior of Trains Excited by a Non-gaussian Vector Valued Random Field

Since 2012, European high speed railway networks are meant to have gone to market. Hence, several high speed trains, such as ICE, TGV, ETR 500, Sapsan..., are likely to run on the same tracks, whereas they have been originally designed for specific and different railway networks. Due to different mechanical properties and structures, the dynamic behaviors, the agressiveness of the vehicle on the track and the probabilities of exceeding security and comfort thresholds will be very different from one train to an other. These maintenance, certification and comfort criteria depend on the dynamic interaction between the vehicle and the railway track and in particularly on the contact loads between the wheels and the rail, which are very hard to evaluate experimentally. Therefore, the numerical simulation is bound to play a key role in this context, as it is able to compute these quantities of interest. Nevertheless, the track-vehicle system being strongly non-linear, this dynamic interaction has to be analyzed not only on a few track portions but on the whole realm of possibilities of running conditions that the train is bound to be confronted to during its lifecycle. In reply to this concern, this paper presents a method to analyze the influence of the track geometry variability on the train behavior , which could be very useful to evaluate and compare the agressiveness of different trains. This method is based on a stochastic modeling of the track geometry, for which parameters have been identified with experimental measurements.