Outline
This immersed-tube tunnel beneath Tokyo Port was completed in 1976.
It forms a crucial link in the Tokyo Port Metropolitan Expressway
loop road that serves
the Odaiba and Tokyo Bay waterfront areas. Continuous growth of traffic
in the Tokyo waterfront area means that traffic flows will eventually
exceed the
capacity of the tunnel. The authorities are therefore currently examining
alternatives to avoid future traffic congestion.
Role of NCC
One possible way of bringing relief could be to augment the Tokyo Port
Tunnel with further tunnels across the port. NCC is a member of the
construction technical consultation committee examining this potential
project. In this capacity we have undertaken feasibility studies
for constructing the additional crossing using the shield tunneling
method. Of particular concern is how the shield tunnel might influence
the existing immersed tube tunnel. We are applying our expertise
to propose solutions to this construction challenge.
Outline