TBM Ruby, the last of six TBMs to be launched on the project, will join TBM Jessie in constructing 2.3km twin railway tunnels beneath Sydney harbour.
The 1,100-tonne machine will tunnel alongside the Anzac Bridge, through the Pyrmont Station site, and under Darling Harbour, before arriving at its final destination at Hunter Street in the Sydney CBD.
TBM Ruby is named after women’s rights activist and Australia’s first radio astronomer Ruby Payne-Scott.
TBM Jessie, which was launched in June, is working on the parallel tunnel and has excavated 615m and installed 2,238 concrete segments.
A total of 460,000 tonnes of material will be excavated and 16,536 segments installed by the two TBMs to construct the tunnels between The Bays and Hunter Street.
The tunnels will form Sydney’s second under-harbour railway crossing.
TBMs Ruby and Jessie are heading towards Pyrmont Crossover and Station caverns, where they will traverse the station cavern before being relaunched towards Hunter Street Station. They are expected to arrive at Hunter Street mid to late next year.
They are mixed shield machines, designed for the Metro West project to excavate in the highly pressurised conditions that are anticipated under Sydney Harbour. Parts of both TBMs came from the TBMs used to construct the Sydney Metro City & Southwest tunnels.
John Holland CPB Contractors Ghella Joint Venture is excavating the under-harbour tunnels and two new station caverns at Pyrmont and Hunter Street as part of the Sydney Metro West – Eastern Tunnelling Package.
Major tunnelling is progressing across the project, with two TBMs completing the 11km tunnels from The Bays to Sydney Olympic Park, and a further two TBMs in the ground to build the 9km tunnels between Sydney Olympic Park and Westmead. Sydney Metro West will double rail capacity between Greater Parramatta and the Sydney CBD. It will make it easier and faster to travel around western Sydney, link new communities to rail services and support employment growth and housing supply.