The facts
Client: Norwegian Public
Roads Administration
Location: Oslo, Norway
Services: feasibility, outline and
detailed tunnel design
Sector: Infrastructure
Project Value: €300m
Start/Completion: 1997 - 2010
The Project
The Bjørvika Immersed Tunnel is the
first in Norway and Capita Symonds has been involved with the
project since 1997 when we first provided advice on the feasibility
of the scheme.
This was followed up with outline design and
detailed design of the tunnel structure, working with Norwegian
consultants Aas Jakobsen. We assisted in the preparation of
the contract documents and have subsequently provided advice and
site support during the construction phase.
The immersed tube tunnel technique is highly
specialised and Capita Symonds is one of only a few consultants in
the world with the necessary expertise to deliver such
projects. The method involves the construction of large box
shaped tunnel elements in dry docks or purpose built basins, which
are sealed with bulkheads then floated up and towed to site where
they are sunk into a pre-dredged trench in the river or sea
bed. The tunnel elements are joined together with a complex
arrangement of watertight gaskets and once backfilled, the road or
railway can be constructed internally.
The immersed tunnel in Oslo is 600m long and
will carry a dual three lane highway under the
harbour. It is part of a much longer network of tunnels
carrying traffic beneath the city on the E20 highway. The
overall scheme cost is in the order of €300m, with the immersed
tunnel contract being worth €124m. The client is the Norwegian
Public Roads Administration and the contractor for the immersed
tunnel is a joint venture of Skanska, BAM and Volker Stevin.
The tunnelling contract is linked to the
opening up and redevelopment of the harbour area, which includes a
new opera house, commercial and residential districts. The
project still has a long way to go however, as once all of the
tunnel elements are in place there will be a lengthy period for
finishing the road construction within the tunnel and fitting the
mechanical and electrical systems required for safe
operation.
The tunnel should be open to traffic in 2010
with the remainder of the harbour development planned to be
complete around 2012.