By Lynda Myer
The TBMs constructing the Sydney Metro Western Sydney Airport southern tunnels are nearing their final destinations.
Already constructed 4.7km and 4.5km of the 5.5km tunnel, TBMs Eileen and Peggy have dug 852,288 tonnes of spoil and installed 32,472 concrete segments in the twin tunnels.
The location of commissioning these two TBMs by CPB Contractors and Ghella Joint Venture is Airport Business Park and they broke through at the Airport Terminal station site and temporary shaft before continuing to tunnel beneath the future Western Sydney International Airport, whereas the Bringelly services facility shaft was their most recent breakthrough, which is being used as a tunneling and construction support site during the delivery of the 5.5km southern metro tunnels.
Considering that the TBMs had to traverse the 10m-diameter shaft for undergoing maintenance before being relaunched to continue tunneling towards the Aerotropolis this process’s time duration was nine days.
Work at the Bringelly site comprising of removing the concrete tunnels ,the machines left behind across the shaft, with access being maintained to supply materials for construction due to the relaunch of TBMs.
Additionally, construction of the 4.3km tunnels between Orchard Hills and St Marys is up to further two TBMs, Catherine and Marlene, that are about 89% and 80% of their journey respectively.
Once inaugurated, the 23km Sydney Metro – Western Sydney Airport will become the transport spine for Greater Western Sydney.
