Rhaetian Railway

The Rhaetian Railway – granted UNESCO World Heritage status in 2008 – is a masterpiece of construction technology and the art of the railway engineer. In Samedan in the canton of Graubünden, four of the Rhaetian Railway lines come together to form the hub of rail network in Oberengadin. To remove the Sper l'En level-crossing in Samedan and separate the roadway and railway, the local authorities arranged to lower the track by up to five metres.

The challenges

The track section is 420 metres long: a stretch of 288 metres is laid as slab track; 100 metres of this are in a tunnel.
The altitude of the village of Samedan is 1700 metres above sea level
Unusual geological conditions are also present: the tunnel and track are located in ground water
Temperatures can fall as low as minus 30 degrees Celsius in the winter months

The Getzner solution

The Rhaetian Railway is the first to use a slab track in the form of a mass-spring system: a 288 m long "trough" that lies in ground water is the key element along the lowered length of track. It has been executed as a full-surface bedded mass-spring system.

To provide complete dewatering of the surface, lateral water channels and four pump pits were installed, two of which are heated during the winter. Getzner also installed strips of drainage matting in the corners along the entire length of the trough to catch any water entering via the joints. Together, these two measures ensure controlled and comprehensive dewatering of the mass-spring system.

Red Rhaetian Railway train on a stone viaduct exiting a tunnel in daylight.

©Rhätische Bahn - Tibert Keller

Advantages for the customer

Quality of life improved in the long term
Efficient vibration and structure-borne noise protection
Extremely effective vibration protection at 1700 metres above sea level
Effective resilient bedding under extreme weather conditions
Under ballast mats to adjust the stiffness of the bedding in the transition areas

From our perspective, the extensive know-how of the Getzner technical team made a very valuable contribution to the successful implementation of the project. On the one hand, they performed the calculations for the resilient bedding of the mass-spring system and the transition areas, while on the other, they delivered a solution that met the stringent vibration requirements as set out in the IEFC specification.