Flat sleepers

Flat sleepers for track

The German Federal Railway Authority (EBA) and the Swiss Federal Transportation Office granted approval in 2014 for the use of flat sleepers on the respective railway networks.

In the course of close collaboration with the staff of Deutsche Bahn it was found that very costly maintenance was repeatedly required at specific locations in the rail network. This is especially the case in places where the ballast level under the existing sleepers is no longer adequate or where man-made structures above or below the railway line restrict the clearance gauge of the railway.

The FFU flat sleeper has already proven itself for a number of years, even on heavily used track with up to 100,000 load tonnes per day.

FFU® with a height of 10 cm

Since 2008 the Vienna Wiener Linien have been routinely installing FFU sleepers with a height of 10 cm. The track of tram line 31 on the Floridsdorf bridge consists of 10 cm high FFU sleepers with a direct fastening. A total of 1,600 metres of track was built with FFU.


Since a large part of the Vienna underground network has polyurethane sleepers from the 1970s/80s and these have reached their life expectancy, a long-term programme is currently under way to replace these sleepers with FFU synthetic wood sleepers.

This is done in ballastless track and in heavy and light mass-spring systems in tunnels.
In Germany, local transport operator Bogestra built a switch with 10 cm high synthetic wood sleepers in ballasted track in 2012.

FFU® with a height of 12 cm

Southeast Bavaria Railway has installed these at overpasses of agricultural and other roads.

Near Hanover, sleepers with a height of 12 cm have been installed on a Deutsche Bahn train line carrying 100,000 load tonnes every day.
In Switzerland, the Rhaetian Railway has been installing 12 cm sleepers at agricultural road overpasses and bridges since 2014.

This started after the BAV (Swiss Federal Transportation Office) approved, in January 2014, operational trials on the use of FFU synthetic wood of heights of 12 cm and more, including in tunnels where wooden sleepers are used.

Use in operational trials in Germany and Switzerland up to 22.5 t axle load and 200 km/h design speed.

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