Work is ramping up on Melbourne’s Metro Tunnel Project, with the launch of the road header machine that will dig the underground cavern for the new State Library Station.
The 118-tonne, 15-metre long machine had to be lowered almost 30 metres under A’Beckett Street in pieces prior to assembly for the commencement of digging this week.
Six road headers – massive excavating machines fitted with mounted cutter heads – will mine out the caverns for the State Library and Town Hall Metro Tunnel stations.
To minimise disruption during the construction of the new State Library Station, access shafts are being built at A’Beckett Street, Franklin Street east and west, and La Trobe Street. These shafts allow machinery, equipment and workers to be transported underground to build the new station in heavily built-up areas.
Victorian premier Daniel Andrews visited the A’Beckett Street acoustic shed this week.
“Whether it’s building the Metro Tunnel, removing level crossings, delivering bigger trains or building the Suburban Rail Loop – we’re delivering the projects Victorians need,” Andrews said.
“We’re not wasting a minute with major construction ramping up on the Metro Tunnel, so we can run more trains more often.”
In 2019, a second road header will start its journey from the A’Beckett Street shaft towards La Trobe Street, and a third from Franklin Street east towards A’Beckett Street, as the three machines work together to form State Library Station.
The equivalent of almost 70 Olympic swimming pools of rock and soil will be excavated by the road headers during the construction of State Library Station, which will be located directly beneath Swanston Street, between La Trobe Street and Franklin Street.
The machines will excavate around 1500 tonnes of rock each day, with the cutter head able to smash through rock three times harder than concrete. Each road header includes a highly advanced computer used to accurately excavate the cavern.
Excavation is continuing within the Franklin St East acoustic shed, with the access shaft currently at a depth of around 30 metres. Piling is currently underway to support the excavation of access shafts at Franklin Street West and on the corner of La Trobe and Swanston streets.