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Metro Tunnel

Roadheaders

A total of seven roadheaders will be used to create the Town Hall and State Library stations in the CBD.

Our roadheaders will work together deep underground to mine the station caverns for our State Library and Town Hall stations.

In line with tunnelling tradition, these road headers are named after females, which is thought to bring good luck to the project.

In July 2019, our roadheaders met 30 metres underground in our first major breakthrough, connecting two excavated caverns that will become State Library Station.

Working under your feet

Roadheaders are massive excavating machines fitted with a mounted cutting head which will mine out the caverns for both State Library and Town Hall stations.

To better respond to the unique ground conditions in the CBD, and to provide more spacious and accessible station platforms, an innovative trinocular design has been proposed for the State Library and Town Hall stations.

A trinocular design combines three overlapping tunnels that integrate the concourse and platforms on a single level to create a wide, central tunnel space, improved passenger circulation and vertical transportation.

Our roadheader fleet is essential in this design, carving out a space for the 19m wide platform before it is reinforced with a combination of sprayed concrete, rock bolts and a final concrete liner.

The roadheaders will advance at approximately two metres per day.

Digging the station caverns

Infographic showing how the roadheaders will dig out stations caverns

Breakthrough

In July 2019, three roadheaders met 30 metres underground in our first major breakthrough, connecting two excavated caverns that will become State Library Station.

Roadheader gallery

Click on any image to enlarge it and use the arrows or your keyboard to scroll through the gallery.