THE Bella Vista factory that will make the concrete rings to line the North West Rail Link’s tunnels is nearly finished, the Minister for Transport Gladys Berejiklian said yesterday.
Watch a time lapse video of the construction of the factory here.
“Next month we expect it will start producing the first of 100,000 concrete segments – which will be assembled underground into 16,000 rings, to be installed as the tunnel boring machines move along the route,’’ Ms Berejiklian said.
“The North West Rail Link is on budget and moving forward rapidly’’
Tunnel boring machines install the concrete tunnel lining rings as they dig and need a constant supply of about 100,000 concrete segments, which are used to create the rings.
Work on this factory at the future Bella Vista station, on the corner of Old Windsor Road and Celebration Drive, began last Christmas.
Ms Berejiklian said tunnelling consortium Thiess John Holland Dragados would recruit about 900 workers from western Sydney for the project in the coming months.
“The North West Rail Link is on budget and moving forward rapidly,’’ she said.
More than 140 tonnes of steel was used to build the frame for the Bella Vista factory, which is 147 metres long, 60 metres wide and 17 metres high at its tallest point.
The building has been enclosed with special acoustic cladding, which will allow the facility to make segments 24 hours a day without adversely impacting neighbouring properties.
All of the infrastructure needed to support the operation of the tunnel boring machines will be set up in the Bella Vista site, including sheds to handle the crushed rock from digging, conveyors, a water treatment plant and a cement grout plant.
VISIT THE STATIONS: Click here to take a tour of all eight stations on the $8.3 billion North West Rail link.
■ Twin tunnels: 15 kilometres of twin tunnels will be built from Bella Vista to Epping — Australia’s longest railway tunnels;
■ Tunnel boring machines: The first of four tunnel boring machines will be in the ground by October this year. Each will weigh more than 900 tonnes – or the equivalent of about 570 Holden Commodores — and be up to 120m long, or almost the length of two A380 passenger jets. Each machine will have a crew of 15 on board per shift.;
■ Weekly cut: On average, 120 metres of tunnel will be cut every week by the tunnel boring machines;
■ Rock type: 60 per cent of boring will be through Sydney sandstone with the rest shale;
■ Sustainability: All crushed rock generated from tunnelling will be re-used, with none going to landfill; and
■ 2.8 million tonnes rock: 1000 Olympic swimming pools — or 2.8 million tonnes of crushed rock — will be generated by tunnelling.
How tunnel boring machines work:
1. Grippers extend out to the rock surface, allowing the front shield and cutting head to move forward. Rock is crushed by high strength alloy steel discs on the cutterhead.
2. Crushed rock is scooped into the machine’s head and on to a conveyor belt.
3. The conveyor moves the rock through the machine shield and out of the tunnel behind it.
4. Precast concrete ring segments are delivered to the ring building area.
5. Concrete ring is built by putting together the precast segments using a special vacuum lifting device.
6. The completed ring, about 1.7m long, is connected to the previous concrete ring then pushed out the back of the shield section.
7. The gap between the concrete ring and the rock is filled with grout, helping to keep water out of the tunnel.
8. The machine moves forward about 1.7m and then the process starts again.