A second tunnel boring machine (TBM) has been put to work on North East Link, digging from Watsonia to Bulleen.
TBM Gillian – named after local pioneering neonatal paediatrician Dr Gillian Opie – is following TBM Zelda which launched in August and has already progressed over 200m. The two TBMs will dig approximately 10m per day and up to 45m underground as they help build the tunnels that will pass traffic under instead of through local suburbs.
The tunnels will be built using 100 per cent renewable electricity, and dirt and rock from the tunnels will be re-used across North East Link and other transport sites where possible.
As they dig the tunnels, the TBMs will install tunnel walls made of approximately 44,000 individual concrete segments made locally in Benalla.
As the TBMs continue their journey from Watsonia, more tunnelling has started between Manningham Road and Trinity Grammar, with five large machines called road headers starting to dig a southern section of the North East Link tunnels.
These machines, some of which have been refurbished after working on the Metro Tunnel, are used as part of a technique called mined tunnelling, involving chipping away at the rock layer deep underground and spraying concrete to support the roof and sides of the tunnel.
As works forge ahead, minor levels of vibration may be experienced in areas very close to mined tunnelling activity, which will be closely monitored and managed to ensure minimal disruption. While the tunnels are being built underground, a huge amount of work is continuing at the surface including tunnel roof construction and building new interchanges and ramps.
Tunnelling across the project will continue until 2026, with North East Link expected to open to traffic in 2028. The project is funded in a joint partnership by the Federal and Victorian governments and will take 15,000 trucks off local roads every day and cut travel times by 35 minutes.
Victorian Minister for Transport Infrastructure, Danny Pearson, said, “Victoria’s missing link has been talked about for decades – we’re getting on with building it to make sure our freeways are keeping up with our growing state.”
Major Road Projects Victoria CEO Duncan Elliott “Victoria’s biggest road project – the North East Link – will move traffic under, rather than through, local suburbs.
“This is a major milestone, with both TBMs – Zelda and Gillian – now tunnelling and building the 6.5km twin tunnels that will form part of the North East Link.
“The 118-tonne road headers have recently completed a 270 metre-long ventilation tunnel in Yallambie and will now get to work digging a section of the road tunnels in Bulleen.”
Image: Major Road Projects Victoria
