Tunnel Boring Machines
Tunnel Boring Machines (TBMs) are large machines that excavate below the ground surface, while simultaneously installing concrete lining units to build a tunnel. Two TBMs have been specifically designed for the Forrestfield-Airport Link by German company Herrenknecht, the world’s leading supplier of TBMs.
There are various types of TBMs to cater for different project requirements. For this project, the TBMs will be Mixshield which use the latest dual-mode technology capable of adapting to variable ground conditions, such as sand, rock and clay, as the machine progresses.
Two TBMs will arrive on site at Forrestfield in mid-2017, where they will be lowered into a dive structure and begin their two-year journey towards Bayswater. During this 8km journey, the TBMs will excavate under Perth Airport and the Swan River reaching up to 30m depth below the surface.
To find out more about how these machines operate, view the TBM fact sheet.