Thousands of concrete segments lining tunnel walls

More than half of the 25,000 concrete segments needed to line Cross River Rail’s twin tunnels beneath the Brisbane river and CBD have been produced.

Wagners Precast facility at Wacol – one of 800 Queensland-based suppliers and subcontractors to benefit from the project so far – has manufactured more than 13,000 segments to date.

Getting these segments underground to form the tunnel walls is no simple task.

The segments are stored at the Wacol facility, before being transported to Cross River Rail’s Woolloongabba site, where they are stockpiled at a range of locations on site.

From there, they are loaded onto a special purpose vehicle and transported in sets of six down into the tunnels and taken to the rear of either Tunnel Boring Machine (TBM).

They are then loaded into the TBM, which installs the segments in rings of six, as they move along the tunnels. Each ring is made up of six segments.

So far, TBM Else has installed about 650 rings, while TBM Merle has installed about 400 rings.

Keep an eye out on Cross River Rail’s social media pages in the coming weeks as we give an in-depth look into the massive logistical effort required to line our tunnels’ walls.

Hundreds of curved concrete segments tacked in pile. It resembles a carpark

Concrete segments fast facts:

  • Six concrete segments are used to create one tunnel ring;
  • 4,157 tunnel rings are required to line both tunnels;
  • 25,000 segments will be produced at Wacol;
  • Each segment is 27 centimetres thick and 1.7 metres long;
  • More than 105,000 cubic metres of concrete will be used to create the segments.