The four TBMs needed for the $11 billion project will be more than 100 m long, weigh up to 1,000 tonnes and be custom-built to grind through Melbourne’s unique ground conditions.
It will take up to 18 months to build the mammoth machines before they’re tested and shipped in segments to Melbourne. They will then be delivered to launch sites at Arden and Domain, where they will be lowered into the ground and reassembled on-site by local workers. They will be in the ground, operating 24/7 in 2019.
As they work up to 40 m below Melbourne’s surface, they will progressively install concrete linings to support the excavated tunnel. Each TBM will include offices, kitchens and toilets, and be operated around the clock by a crew of around 15 people.
As work ramps up, thousands of people flocking to the CBD in the lead-up to Christmas will be able to watch the works underway at City Square.
Plans were underway to install windows in the giant timber fences along Swanston St to create a viewing area where people can see the former underground City Square car park demolished and removed.
Works are underway at City Square where construction crews will dig 11 stories below the ground to build a new underground station. The Metro Tunnel project will free up space in the City Loop to run more trains, more often across Melbourne.
The project will create nearly 7,000 local jobs and will be completed in 2026.
“We’re building a world-class, turn-up and go train system for Victoria and will use the world’s best to get the job done,” Premier Daniel Andrews said. ““These giant custom-made TBMs will work day and night beneath the ground, building the Metro Tunnel to run more trains, more often, across Melbourne.”