A scheme to relieve commuter congestion in the centre of
Melbourne by means of a new rail was initiated in the early 1970s.
To the north and east of the city centre this provided three new
stations connected to an existing suburban rail terminal in the
south and west by a four-track rail line.
In partnership with Hatch Associates and Jacobs Associates, Mott
MacDonald was appointed to carry out a planning study of the
overall project, reporting on construction and equipping of the new
system. The study included a review of all equipment installation,
systems operation, and for a project network drawn up to allow work
to commence immediately. The team then proceeded with the detailed
design and construction supervision of all civil engineering works
for the system.
Four 3km rail tunnels of 6m internal diameter were constructed,
together with a 730m two-track viaduct and three stations. Lower
platforms at Parliament, the deepest station, are located 37m below
ground. Here tunnels were driven through fractured Silurian
mudstone and sandstone in all stages of weathering.
Museum station was built in an exceptionally large and deep
excavation supported by steel struts bearing on bored king piles.
Flagstaff station was constructed entirely below ground using
raise-boring methods to form concrete sidewalls between top and
bottom headings.
In addition to the civil engineering aspects, the team provided
project management services and co-ordinated all activities
concerned with the scheme.
