The vibration field of a railway line in a 180 m linear cutting was measured and modeled to predict its impact on a future real estate program, as a work package of ECOCITE II, an urban innovation program. For decades, vibration levels due to rolling stock have been evaluated in the vicinity of tracks on the vertical z axis, at one or a few points, supposed to be representative of the entire vibration field around the tracks. When the size of the project is rather large, this assumption is incorrect, especially if the site is located near a train station, where stresses in the tracks can vary a lot depending on the direction of the train, i.e. depending on acceleration or deceleration of the train. This paper presents vibration measurements performed in different directions at six positions before the construction of any building (free field conditions) along the tracks. Steel spikes were used to mount vibration sensors and results suggest that resonnances can appear at some measurement points. In this paper, a procedure similar to the FTA method is used to further investigate this behavior. Furthermore, the attenuation of ground vibrations as a function of distance from the track can be used to evaluate the loss factor in the ground based on a comparison with a 2.5D BEM model of the ground including the different layers. The model is then used to identify equivalent forces in different directions (i.e. vertical, perpendicular and parallel to track directions) associated to train passage to lead to similar vibration transmission behavior in the ground.
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