The first TBM has broken through into a purpose-built cavern at Wooloowin, halfway through its 2.5km drive to Lutwyche on the Brisbane Airport Link project.
Nicknamed ‘Rocksy’ it and its twin ‘Sandy’ were the two largest machines ever used in Australia at 12.48m in diameter, 195 metres in length and weighing 3600 tonnes.
“Sandy, is expected to break through into the Kedron caverns next month, with the TBMs scheduled to complete their 2.5 kilometre journey by the middle of the year,” said Gordon Ralph, Thiess John Holland project director. “Once tunnelling is complete the cutterheads for the massive Tunnel Boring Machines will be buried underneath the tunnels they have created.
“The two TBMs were custom built for the Airport Link project and this solution will reduce the complexity involved in removing the cutterheads, while avoiding the need for additional surface work in the Lutwyche area,” he said. “The last 180 metres of each machine, will be removed after the front ends are concreted into the burial pits.”
Over 70 per cent of the project was complete as T&TI went to press.
