The first of four tunnel boring machines (TBM) needed for construction of Norway’s Follo Line rail tunnel is now being assembled on site.
Last week the cutterhead and leading parts of the first northbound TBM were transported down the 1km access tunnel to a specially excavated assembly chamber.
The 9.9m diameter Herrenknecht TBM will be used by the Acciona Ghella Joint Venture (AGJV) to drive tunnels on the Follo Line which will connect Oslo and Ski by rail.
The second northbound TBM will also be assembled within the chamber while the remaining two TBMs will be assembled in a similar chamber at the other end of the tunnel bore.
The first TBM is expected to start work in September and will bore 9km of tunnel towards Oslo through rock. Progress, once the launch is complete, is expected to be in the region of 12 to 15m per day.