Application of NDT to railway track inspection

Track failures are one of the main problems that railroads have faced since the earliest days is the prevention of service. The lack of a systematic monitoring brings to the impossibility to produce an effective long term railway track management system, by allocating budget where emergencies come. Latest technology can improve the rail inspection with higher cost of the equipment. The great advantage is related to the speed and precision of the measurement, avoiding to interfere with the normal use of the infrastructure. Despite that, in local railway with reduced gauge, the use of traditional monitoring systems at high speed is not feasible. In this framework the monitoring of the track with alternative non-destructive techniques (NDT), such as GPR and LWD are promising for ballast and track stiffness inspections. In recent decades, these devices have already proven their effectiveness in the field of road pavement engineering and prospects are the same in the rail sector which is increasingly growing. This paper details, with a trial on a site of investigation, the opportune and effective use of the equipment and their performance. As future work the use of NDTs is expected to affectively contribute to a creation of a reliable monitoring system for preventive maintenance strategies of railway asset and Quality Control of track works, as well.