What is a complete track replacement?
Complete track replacement involves the removal and replacement of all components of the track structure, including the rails, ties (sleepers), fasteners, and ballast, down to the subgrade or subballast layer, to restore the track to a like-new condition. This is a major undertaking typically performed when the track has reached the end of its service life or has deteriorated to the point where it can no longer be economically maintained. The process typically begins with the removal of the existing rails, ties, and fasteners. The old ballast is then removed, and the subgrade or subballast layer is inspected and repaired or improved as necessary. New ballast is then installed and compacted to provide a stable foundation for the new track. Finally, the new ties, fasteners, and rails are installed and aligned to the required specifications. Complete track replacement can be performed using specialized track renewal equipment, which automates many of the tasks involved, such as removing the old track components, distributing the new components, and installing the new track. Complete track replacement is a costly and time-consuming process, but it can significantly improve track safety, reliability, and performance. It also reduces the need for frequent maintenance and extends the life of the track. For example, if a section of track has been in service for many years and the rails, ties, and ballast are all worn and deteriorated, complete track replacement may be the most cost-effective way to restore the track to a safe and reliable condition.