TRACK RENEWALS ON THE SNCF

Renewal of a track proves necessary when the day-to-day maintenance operations no longer make it possible, taking into account the volume of the traffic and aging of the equipment, to conserve adequately the geometrical characteristics of the track in question. Apart from the replacement of obsolete equipment, complete renewal of track and ballast makes it possible to provide the new superstructure with the benefits of all the technical progress associated with modern track. The development of techniques tending towards mechanisation has made it possible to obtain better performance and markedly improved quality of work. Today, the advanced technology of the renewal trains also makes it possible to limit the operating constraints on the main routes, by reducing track possession, and by increasing the running speed over the working site. After replacement, the levelling of the new track and removal of constraints allow traffic to run once again at the maximum speed of the line. The results obtained particularly from the economic point of view constitute for the SNCF a decisive stage in the new track maintenance policy.