N04/06 Galgenbuck Tunnel, Schaffhausen

The 1,138 m long Galgenbuck Tunnel feeds cars from Klettgau onto the motorway at the Schaffhausen South junction. It passes beneath Neuhausen am Rheinfall, keeping through traffic away from the town itself. Commissioned by the Swiss Federal Roads Office (ASTRA), Implenia worked in a consortium with Walo Bertschinger to build the main section (Lot 3: building the tunnel shell). Implenia had a 50% stake in the consortium and was the commercial and technical lead. The tunnel was handed over to the customer in July 2018. Delivered on time to impeccable quality, the Galgenbuck Tunnel is an excellent reference project for further tunnel construction projects in Switzerland and abroad. The two-lane tunnel’s excavation profile opens up in the portal areas and by the service bay from 120 m², to a maximum of 230 m². The excavation, most of which has been done by drill and blast, has produced around 160,000 m³ of spoil. The need to tunnel beneath a built-up area and a rail tunnel presented a particular technical challenge. Access to the tunnel was only possible from one side for the whole of the entire five-year construction period.