Track – Bridge Interaction on High Speed Railways – the ONCF Experience

Abstract

This paper aims to describe the Moroccan experience on Track – Bridge interaction in railway domain. In fact, that phenomenon may induce a general track instability compromising train security if it’s not taken into account in the study phase. To that end, a numerical method, used to compute the additional longitudinal stresses on a continuously welded rail (CWR) mainly associated to relative displacements between track and deck on account of temperature variations, is presented. Therefore, the conditions of laying an expansion device will be concluded, particularly when the additional rail stresses exceed the maximum limit values defined on the current standards. An application of that method will be performed on MHARHAR viaduct where a non-compliance of track dilatation device laying was noticed. This study will emphasize the beginning of a track grid general instability due to ballast layer deconsolidation, the all based on a track geometry measurement. This study may be widely used in order to conceive properly a bridge supposed to receive a CWR track.