Zürich Cross-City Link

The Letzigraben (1156 m) and Kohlendreieck bridges (394 m) form an integral part of the Zürich Cross-City Link project that connects Altstetten with Zürich main station and Oerlikon. The two bridges form the westwards exit from the new, underground Löwenstrasse station.

Construction work began in 2008 with "re-routing" of track sections in the track field before Zürich main station. From 2009, a total of 23 piers were erected. The piers, which are a maximum of 16 metres high, are founded on bored piles up to 45 metres long. The bridge superstructure was built by means of advance scaffolding, which was assembled in autumn 2011. A structural defect required the installation of slab instead of ballasted track from November 2013. This was because six to eight tension cables had to be pulled in across the carriageway above each of the 23 piers and fixed on the outside with anchor heads to ensure stability. The tension cables resting on the bridge trough had to be concreted in, which meant that a conventional ballast superstructure could no longer be installed due to the lack of space. Therefore, for the first time in Switzerland, a slab track of the "Low Vibration Track" (LVT) system was installed on a bridge.

SBB commissioned RUBI Railtec for this project change. The big challenge was to find a technically feasible solution and to have it approved by the Federal Office of Transport (FOT). Furthermore, RUBI Railtec carried out the tendering of the construction work and to closely accompany its completion as site manager. Despite the project change, the bridges were able to go into operation as planned at the end of 2016.

Image: © SBB/CFF/FFS