Work is set to begin on the construction of a specialised precast concrete factory at Marrickville in Sydney that will provide more than 99,000 concrete segments which will line the inside of the new metro railway tunnels.
108 giant moulds have already arrived on site that were originally used to deliver the twin 15km Sydney Metro Northwest tunnels between Bella Vista and Epping, and are being recycled for the next stage of Sydney Metro tunnelling.
Tunnel builders John Holland CPB Ghella will reuse the equipment and plant from the precast concrete factory they built at Kellyville in 2014, which produced 98,184 segments for the Sydney Metro Northwest tunnels.
The factory will start making the concrete segments in the first half of 2018 and is expected to make an average of 280 a day, with up to 120 workers employed at the site.
The new facility will open before the tunnel boring machines start work by the end of 2018 so a stockpile of segments can be created for when the tunnel boring machines start work.
The moulds are designed to cast segments which each weigh about four tonnes and measure 3.5m long and 1.7m wide. Some new moulds will be needed for segments under the harbour and for a few tighter bends.
Two of the five massive tunnel boring machines delivering the Sydney Metro tunnels will start work from Marrickville and dig 8.1km to Barangaroo before the end of 2018.