Due to their age, more than half of the 115 tunnels in the Rhätische Bahn (rhb) network currently require renovation. For this purpose, the railway operator developed a new, standardised restoration method: The ‘normalbauweise tunnel’. This improves the quality and economy of the tunnel renovations, increases the safety standard and extends the service life of the tunnels to 70 to 100 years.
A good and very successful method – which Rhomberg Bahntechnik was able to improve once again for the Bergünerstein Tunnel: for the conversion from ballast to the definitive slab track, the railway engineering specialists were able to convince the RhB's representatives with the IVES system adapted for the ‘Normal-bauweise’. Here, precast concrete elements are used to a large extent, which enable a daily output of 20 metres during the seven-hour night closures. This solution is more economical for the client and also brings some technical advantages: with a smaller excavation cross-section, meaning less bed lowering, and a more stable track position, the RhB's services such as the installation of auxiliary bridges or the supply of superstructure materials are reduced. The complete tunnel widening with a daily capacity of 3.5 metres can subsequently be carried out during night intervals.
The project volume is approximately CHF 11.5 million. Construction began in autumn 2019, with completion scheduled for 2021. Lukas Herburger, Project Manager: “This solution for the maintenance of the Bergünerstein Tunnel once again proves the reputation of Rhomberg Bahntechnik and the entire Rhomberg Sersa Rail Group as a full-service provider in railway technology with a strong customer focus and innovative strength.”