Sydney Metro - Site Investigation and Ground Characterisation for the Sydney Harbour Crossing
Sydney Metro is Australia’s largest public transport project, extending 65 km from the northwest of Sydney, under the iconic Sydney Harbour, through the CBD and then towards Bankstown to the west. The harbour crossing is a key element of Sydney Metro. Limited geotechnical information existed prior to the project. As such, detailed geophysical and geotechnical investigations to facilitate early planning and design work were undertaken for three harbour tunnel alignment options, which would involve either full rock face excavation by Tunnel Boring Machine, mixed face Tunnel Boring Machine excavation or the installation of immersed tubes. Following best practice, extensive geophysical and geotechnical data has been collected to characterise the ground below the harbour floor, identifying possible geotechnical risks in tunnelling beneath the harbour.