By rosebell
Three tunnel boring machines (TBMs) are now excavating the twin tunnels for Melbourne’s Suburban Rail Loop (SRL) East, with a combined 138m of tunnelling completed since work began in September.
On the northern section, the Terre Verde consortium, comprising Webuild, GS Engineering and Construction, and Bouygues Construction Australia, has launched TBM Hacia. The machine joins TBM Alice to excavate the twin tunnels between Burwood and Glen Waverley.
Tunnelling has also commenced on the southern section, where the Suburban Connect consortium — CPB Contractors, Ghella and Acciona — has launched TBM Aayushi from the Clarinda site to excavate towards Glen Waverley.
A fourth machine, TBM Belinda, is currently being assembled at Clarinda and is expected to launch soon.
Umbilical launches accommodate confined sites
Due to space constraints at the launch sites, the TBMs are being deployed using an “umbilical” launch method. The front sections begin excavating first, while the remaining components of each machine are progressively assembled behind them.
Construction is also advancing at surface level. At Burwood, crews are excavating the site for the new SRL station and preparing a second TBM launch site. Two additional machines are expected to launch from there and head north towards Box Hill next year.
At Clarinda, crews are constructing an acoustic shed over the launch site to limit noise, light and dust impacts on nearby residents. Work is also under way to install excavated-material removal systems and power cabling for the TBMs.
Eight TBMs planned for SRL East
Eight TBMs will be deployed across the project: four earth pressure balance machines (EPBMs) manufactured by CREG for the northern section and four machines supplied by Herrenknecht for the southern section.
All TBMs will be powered by 100% renewable electricity. The twin tunnels will run at an average depth of approximately 26m.
The SRL East project comprises 26km of twin tunnels connecting six new underground stations at Cheltenham, Clayton, Monash, Glen Waverley, Burwood and Box Hill.
More than 4,300 people are working on the project, which is a major part of Melbourne’s planned orbital rail network.
