All five TBMs are now underground and at work excavating the 15.5km City and Southwest extension to the Sydney Metro in Australia. Supplied by Herrenknecht, the five machines include four double-shield TBMs, and a multi-mode machine for excavation under Sydney Harbour, a route that will require boring through a section of Harbour sediment. The specialised machine was the last to begin work, departing from its Barangaroo launch site on the south side of the Harbour in early August 2019.
In addition to the twin tunnels, the new Metro line includes six new underground stations: Crows Nest and Victoria Cross to the north of the Harbour, and Barangaroo, Martin Place, Pitt Street, and Waterloo to the south (Fig 1). The tunnels, stations and excavations works package for the project was won by a John Holland-CPB Contractors-Ghella JV in June 2017 at a contract value of AUD$2.8 billion. The contract also includes a launch portal at Marrickville and a temporary TBM retrieval shaft at Blues Point. Bechtel is the Delivery Management Partner for the client, Sydney Metro.
The multi-mode TBM boring the first tunnel under the harbour was retrieved from the shaft on the north side last week.
It was put on a barge and taken back to the south (launch) side for maintenance, ready to bore tunnel 2.
Amazing productivity
Is it possible to upload/send images ?
@KateDemonstration
You can post a link to images.
Twin rail tunnels are being bored under Sydney harbour for a new metro line that runs from north-west via the city to the south west.
A multi-mode TBM that can handle water pressure and silt is being used under the harbour.
It was launched from the south side in Aug 2019 to bore the first tunnel.
The TBM was extracted from the access shaft on the north shore for transfer by barge back to the launch site on south side.
Some pics are here.