Strabag buys shield machines for Koralm

Aker Wirth won a tender to supply the two telescopic shield machines for the 32.5km Koralm tunnel in Austria, part of the high-speed rail link between Graz and Klagenfurt.

Each machine has a 9.93m diameter and will be used at the approximately 20km long KAT 2 section of the tunnel, starting in October 2012.

The cutter head is driven by electric motors with an overall power rating of 4,800 kW and the maximum cutting torque is 30,000 kNm, according to Aker Wirth. “We have continually strengthened our technological leadership, in particular in hard rock,” said Christoph Kleuters, Aker Wirth CEO. ?

TBM back-ups will be delivered and constructed by the Rowa Tunnelling Logistics AG from Switzerland. The entire tunneling system is approximately 160m long and weighs in excess of 1,800t.?

Koralm wil comprise two parallel single-track tunnel tubes, and the only access to the underground construction work areas is by a 60m deep shaft.