Two massive tunnel boring machines (TBMs) that will dig the West Gate Tunnel will arrive in Melbourne in mid-December.
The government said a shed is being built at the Yarraville site to process the thousands of tonnes of dirt and rock that will be excavated during construction for the tunnel’s northern portal.
The steel frame is going up for the 90m x 180m spoil shed at the Yarraville tunnelling hub site, while work is also well underway at the northern portal site to build the tunnel entrance, where the two TBMs will be launched.
The massive TBMs will be 90m long, weighing up to 4000t each and standing 15.6m in diameter — as tall as the top of the dome at Flinders Street Station.
The first TBM will arrive early 2019, and will be the first time a full-scale TBM has been used in Victoria.
Two huge retaining walls have been built either side of the tunnel site, with around 1000 support columns driven into the ground to help keep workers safe on site.
Crews are installing a steel structure inside the huge launch site to provide additional support for the retaining walls which in turn supports the soil at the sides.
To assemble the TBMs, some of the largest gantry cranes ever built in Australia, with up to 500t lifting capacity, will be used.
Spoil from the tunnel will be moved from the TBM to the spoil shed via a covered conveyor, where it will be safely loaded onto covered trucks inside the shed.
The government said the West Gate Tunnel Project will provide a vital alternative to the West Gate Bridge, cutting travel times, taking trucks off local roads and creating 6000 new jobs for Victoria.
Victorian Minister for Transport Infrastructure, Jacinta Allan, said, “The massive TBMs will be working 24/7 to dig the tunnels that will finally provide a much-needed alternative to the West Gate Bridge.”
Member for Williamstown, Melissa Horne, said, “The West Gate Tunnel will bring enormous benefits to our community, slashing travel times so locals can get home sooner and safer, and improving bike paths and trails for cyclists.”