On November 29, 2017, the cutterhead of the Single Shield TBM S-1012 cut precisely through the last meter of rock. The new Bözberg Tunnel between Schinznach-Dorf and Effingen in the Swiss canton of Aargau was completed. From June to November 2017, with daily best performances of up to 40 meters, the tunnelling crew took only five months for 2.5 kilometers with the Herrenknecht machine.
The contractor's success at Bözberg marks a milestone on the Swiss traffic planners' journey toward a sustainable increase in rail capacity on the north-south Gotthard axis. To enable the transport in future of trains with 4 meter high semi-trailer trucks over the entire distance of this highly frequented transit route, the Swiss Federal Railways SBB is investing in numerous new constructions and extensions between Basel in the north and Chiasso in the south.
The largest single project of the 4 meter corridor is the new Bözberg Tunnel, which replaces its existing but too small predecessor. In future the parallel old tube will be used as a service and rescue tunnel. The environment and residents will be relieved of several million tonnes of CO2 when freight traffic can be increasingly shifted from road to rail with the commissioning planned for 2020.
S-1012's main drive is a real rarity. It was already installed in the TBM – serial number at the time S-56 – for the drive of the old, eastward-running Bözberg road tunnel between 1990 and 1993 and has meanwhile helped several hard rock tunnel projects to breakthrough. This is impressive proof that thanks to professional remanufacturing, premium quality TBM components can be used multiple times even over a longer period of time.