Railway ditches, drainage

• Drainage ditches and drainage channels must be cleaned or newly constructed.
• Old installations (e.g. axle counters, signalling devices, hot axle-box detectors) and other obstacles must be removed.

Cleaning, formation rehabilitation

The ballast should be cleaned before the track is renewed to protect the material of the new track panel. If necessary, the substructure must also be renewed and a formation protective layer installed.

Plasser & Theurer also offers a range of suitable machine systems for this purpose (Plasser FormationLiner).

As a variant, ballast cleaning and track renewal can be carried out in a single pass with a single machine(see page 42).

Ballasting, measuring, tamping after ballast cleaning or formation rehabilitation

• Track ballast is unloaded from self-unloading wagons or material conveyor and hopper units (MFS). It is then distributed with a profiling machine.
• The first layer of ballast (also known as sub-ballast or base ballast) can be laid directly using ballast cleaning or formation rehabilitation machines.
• To use a mechanized maintenance train (MDZ) afterwards, the track must be measured manually or by machine.
• Use of the MDZ, consisting of a levelling, lining, and tamping machine (e.g. 09-3X Dynamic) with an integrated Dynamic Track Stabilizer and a ballast management system (e.g. BDS). The MDZ is used to tamp the old track and align it with a lifting and compacting pass. The ballast bed is also profiled.