Tunnelling hits halfway mark with TBM breakthroughs
Posted: 23 Sep 2020
The Metro Tunnel Project’s rail tunnels are now halfway to completion, with tunnel boring machines (TBMs) Joan and Meg finishing digging between the tunnel’s western entrance in Kensington and the site of the new Parkville Station late last week.
The third TBM, Millie, completed tunnelling between the new Anzac Station site under St Kilda Road and the eastern tunnel entrance in South Yarra on Friday. The fourth TBM, Alice, is just weeks from completing a parallel route.
The TBMs have so far excavated more than 364,000 cubic metres of rock and soil and installed more than 30,000 individual concrete segments, each weighing 4.5 tonnes, to line the tunnel walls as crews worked around the clock with stringent health measures in place.
Both TBM Meg and TBM Joan, which broke through at Parkville Station in late August, are being moved through the station site before being cleaned and recommissioned.
TBM Joan will be relaunched in the coming weeks to dig towards the new State Library Station, with TBM Meg following soon after as they make their way towards the heart of Melbourne’s CBD.
TBM Millie’s cutterhead and shield will be lifted out of the South Yarra tunnel entrance site by crane then transported to the Anzac Station site. The rest of the TBM will be pulled back through the tunnel to Anzac Station, then reassembled and relaunched towards Town Hall Station later this year.