Australia’s Torrens to Darlington (T2D) project is set to achieve a major milestone this week with the launch of the last two TBMs.
TBMs Catherine and Elizabeth are in the final stages of preparations and are expected to start excavating in the coming days, joining TBM Mary, which has already carved around 100m beneath South Road.
It is the first time in Australian history that three large-scale TBMs have tunnelled simultaneously on the same road project.
Together, the trio will excavate around five million tonnes of spoil as they construct the Northern and Southern Tunnels in South Australia.
The spoil will be removed by conveyor and transported by road to a reuse site at Gillman.
Around 7.5 million tonnes of spoil is expected to be generated across the whole T2D Project, including approximately 5 million tonnes from tunnelling and a further 2.5 million tonnes from civil works.
The 15m-diameter, 100m-long TBMs are the largest pieces of construction equipment ever used in South Australia.
In July TBM Mary was launched from the Southern Precinct at Clovelly Park to build the first of the 4.5km twin Southern Tunnels. TBM Catherine will be launched from the same site.
Further north, TBM Elizabeth will commence work from the Central North Precinct at Hilton to excavate the first of the 2.2km Northern Tunnels. After completing the first drive, the machine will be turned around and reassembled for the southbound return journey.
Tunnelling across the project will take up to two years.
The A$15.4bn (€9.35bn) T2D project is the final 10.5km section of the North-South Corridor, and will complete 78km of non-stop, traffic light-free motorway between Gawler and Old Noarlunga.
The T2D Alliance of John Holland, Bouygues Construction, Arcadis Australia, Jacobs and Ventia is delivering the project on behalf of the South Australian and Australian governments.
