Développement d'un outil numérique pour la définition des conditions de circulation d'un matériel roulant sur la voie ferrée d'un point de vue de la fatigue du rail

In the context of railway interoperability, new trains are allowed to move on the french railway network and may have different designs from standard trains. Thus, it is important to complete the current approach for rolling stocks admission on the railway network, which is defined in the SNCF technical baselines. Moreover, with the fourth railway package, railway companies have to manage vehicles admission. However, even if computation rules for traffic conditions are suitable for SNCF experts, they are hardly exploitable by railway companies. The current technical beasline is based on Demaux rules, established in 1944, which give a classification of railway tracks regarding to flexural resistance. It has evolved with feedbacks to comply with the track structure evolution. The need is thus to adapt the computation rules for traffic conditions to new rolling stocks. Also, an optimization of the current approach is necessary. The numerical tool developed in this work answer these issues. It proposes an efficient methodology based on numerical simulation to evaluate rolling stocks admission from a rail fatigue perspective. It includes a finite element model of the track, a multibody model of the vehicle, track defects and a fatigue criterion. The industrial need for this tool requires lightweight models. Thus, a beam-like structure model for the track and a linear multibody model for the vehicle were developed. Concerning the fatigue development, the Dang Van criterion was selected. The same strategy of reducing the computation time was followed. The ADMM algorithm to solve an optimization min-max problem for the fatigue problem was implemented. After verification, the tool results were compared to the technical baseline results. Similar results were found with no fatigue initiation in the rail.