The largest railway project in Norway
The contract includes the design and construction, through an EPC, of twin tunnels with an internal diameter of 8.75 m, performed with 4 tunnelling machines, each measuring 19,5 km long.
Once completed, the twin tunnels – designed for trains reaching up to 250km/h – will be the longest railway tunnels in Scandinavia.
The tunnels are each 19,5 km long and have an internal diameter of 8.80 m. They have been dug into the rock by four double shield tunnelling machines.
This is the second and largest of the four EPC (turnkey) contracts included in the Follo Line project, the largest infrastructure project in Norway so far.
The works performed with the tunnelling machines start in the middle of the route, where the facilities serving the keystones and concrete plants are located. Access to this area, where a rescue area and two caverns for the assembly of the tunnelling machines have been installed, is carried out through a series of tunnels built by digging and blasting. The tunnel’s lining is composed of around 20,300 prefabricated rings, with seven keystones each, measuring 40 cm thick.
To link the cities of Oslo and Ski, creating the backbone of intercity development towards the south of the Norwegian capital.
Promoting economic development in the region
The longest railway tunnels in Scandinavia