This photo of a Deutsche Bahn train running through on tracks almost covered by floodwater is quite extraordinary, but when I looked closer it at I found something else I had never seen before – Y-shaped railway sleepers. So that’s the story there?
Luckily Wikipedia has a short write up on them.
An unusual form of tie is the Y-shaped tie, first developed in 1983.
Compared to conventional ties, the volume of ballast required is reduced due to the load-spreading characteristics of the Y-tie. The cross section of the ties is an I-beam.
Noise levels are high but the resistance to track movement is very good. For curves the three-point contact of a Y steel tie means that an exact geometric fit cannot be observed with a fixed attachment point.
As of 2006, less than 1,000 kilometres (621 miles) of Y-tie track had been built, of which approximately 90 percent is in Germany.
Along with a photo showing Y-shaped sleepers beside conventional track.
A section of Y-shaped sleeper tracks before the ballast has been laid.
And a close up view of in-service Y-sleepered track.
But who developed these unusual Y-shaped sleepers? Wikipedia led me to their German name “Y-Stahlschwellen” – which let me to Hyperion Verwaltung GmbH, who details the history of them.
Considering the many advantages of steel sleepers, consideration was given to a truss construction for track construction, in which steel sleepers would be inserted as struts between the running rails. The rails rest on the gusset plates and form the upper and lower chords. Such a track never came to fruition, as the track frame proved too rigid and unworkable for curved track sections.
The “truss concept” was revived and further developed by Jürgen Frenzel, a graduate engineer, and led to the development of a “dissolved” truss structure with Y-shaped steel sleepers. Jürgen Frenzel is therefore credited as the inventor of this Y-shaped steel sleeper superstructure; from 1983 onward, Günter Fasterding joined as co-developer and inventor.
Jürgen Frenzel first looked for a suitable support profile for the new steel sleepers. The Peine beam IB 100 S-1 was chosen because it met the requirements for producing Y-shaped steel sleepers. After selecting the support profile, the forming process had to be carried out. Through cooperation, the Peine-Salzgitter AG steelworks succeeded in obtaining cold-formed sleeper beams that, when placed side by side, form the shape of the letter “Y.”
With suitable rail support and fastening, the first Y-shaped steel sleeper track was built in 1984 at the Peine-Salzgitter steelworks. The first load tests on the Y-shaped steel sleepers in ballast and on slab track were conducted there under the supervision of the Munich Railway Control Center (BZA). These tests were supplemented by derailment and repair tests.
And their early rollout.
1986: 1,000 metres of track of the Deutsche Bundesbahn (DB) on ballast and asphalt base courses on the H–BS line.
1987: Main line and station tracks of the East Hanoverian Railways (OHE) and equipment of a main line track of the East-West S-Bahn S8 of the DB Netz with galvanized Y-steel sleepers on asphalt base courses in the Linderhauser Tunnel.
1989: Switches with Y-steel sleepers in Zurich main station and switches (area of the Deutsche Reichsbahn)
1993: The gap at Kaliningrad Central Station (formerly Königsberg) was closed. Y-shaped steel sleepers for standard, broad, and double gauge tracks were installed.
However 30 years on, the Y-shaped sleepers still seem to be a niche product – but still offered by ThyssenKrupp Schulte GmbH as part of their range.
Safety and cost-effectiveness even on the most demanding routes: This is what our Y-shaped steel sleeper stands for, which has been used in European railway networks for 30 years. Its advantages include a larger footprint, optimized track stability, and a significant reduction in the number of sleepers required and the ballast cross-section.
The smaller ballast cross-section, resulting from the geometric shape of this sleeper, creates a higher resistance to lateral displacement and improved frame stiffness of the track grid compared to the classic superstructure – conditions that make conversions possible even without further investment.
The preferred areas of application include narrow routes and routes with many constraints such as bridges, platforms or tunnels, where the specified height of the top edge of the rail cannot be achieved without complex earthworks, subgrade widening or land acquisition.
We manufacture Y-shaped steel sleepers for track gauges from 750 mm to 1520 mm and various rail types. We also design special applications such as rack and narrow-gauge railways, multi-rail tracks, temporary bridges, guardrails, and safety and guidance systems.
The range of applications extends from light mountain railways and mainline railways according to European standards to heavy-duty railways with 38 t axle load overseas.
Further reading
- Datasheet for Y-shaped sleepers by ThyssenKrupp Schulte (German language)
- Book on Y-Stahlschwellenoberbau by Hestra-Verlag (German language)
- Photos of Y-shaped sleeper track across Europe (German language)
