Sydney Metro is Australia’s largest public transport project. Set to transform transportation in the harbour city by 2030, the network will encompass four metro lines, 46 stations and 113 km of new metro rail. Robust support systems for tunnelling machines, information management and segment liner systems are crucial to the success of this huge project.
Sydney Metro will transform transportation in Australia’s largest city by providing fast, reliable metro services to connect different areas of the city. Stations will be fully accessible, with plans for trains every two minutes, a service level unmatched in Sydney. The metro aims to accommodate around 40,000 passengers per hour, comparable to the world’s top metro systems. The first phase, ‘Sydney Metro Northwest,’ was opened in May 2019 and is 15 kilometres long and has eight stops. The second phase, ‘Sydney Metro City & Southwest,’ adds 15.5 kilometres of twin tunnels. By 2024, Sydney will have 31 metro stations and a 66 km standalone metro system, paving the way for a revolution in urban travel.
Tunnelling for tomorrow
Tunnelling contractor, John Holland CPB Ghella Joint Venture (JHCPBG), used five Herrenknecht tunnel boring machines (TBMs) to excavate 31 kilometres of tunnel for the first two phases. Four double shield TBMs excavated the sections north and south of Sydney Harbour whilst a mixshield TBM dug its way under Sydney Harbour, with an overburden of up to 35 metres to the bottom of the harbour and water depths up to 40 metres. Station cavern construction and other sections of the tunnel required 13 roadheader machines and seven rockbolter rigs.
Trend-setting navigation and monitoring systems
To support the project, VMT provided equipment and site support for the TBMs, roadheaders and rockbolters with various navigation systems tailored to each tunnelling system type, as well as its Segment Documentation System (SDS). VMT’s TUnIS navigation software was also used to support the navigation systems including:
- TUnIS Navigation for each double shield machine
- TUnIS Navigation for the single shield machine
- TUnIS Navigation systems for each roadheader
- TUnIS Navigation systems for each rockbolter
Alongside this well proven equipment, we introduced the TUnIS.mono cam, a tool designed for double shield TBMs that determines the front shield’s position in 3D relative to the gripper shield. Traditionally, this required a system with multiple components like lasers and inclinometers. The TUnIS.mono cam replaces this with a single camera and marker system, reducing space requirements and installation complexity. Complementing the main, laser-based navigation system, it determines the front shield’s position based on the data from the gripper shield. Using photogrammetry, markers on the front shield are captured by camera to allow precise 3D calculations which streamlines TBM navigation, making it more efficient and user-friendly.