Two Herrenknecht double-shield, hard rock, gripper-type TBMs have been ordered to build Sydney’s next metro rail tunnels as part of the Sydney Metro West project, with the first machine set to be in the ground before the end of this year.
The two TBMs are part of the $1.96bn Central Tunnelling Package awarded in July to the Acciona Ferrovial Joint Venture, which has contracted Herrenknecht to design, build and deliver the TBMs following a global tender process.
Each TBM will tunnel an average of 200m per week and will be operated by a team of 15 workers per shift as they dig the 11km of twin tunnels from The Bays to Sydney Olympic Park.
These are the first of six TBMs being used to build the 24km tunnels from the Sydney CBD to Parramatta.
The two borers are 1,266 tonne, 165m long, and are designed to excavate through sandstone and shale.
These TBMs will be specifically built for the conditions they will meet on this job, with design improvements taken on board from the experience of building more than 30km of tunnels for Sydney Metro Northwest and City & Southwest.