A tunnel boring machine (TBM) called Kora broke through at the end of the second of two tunnel tubes.
Porr is building the third construction package for the 33km tunnel under the Koralpe mountain range project. The €297m (£267m) contract involves the construction of two tunnel tubes with a total length of 21km.
Conventional drill-and-blast and excavation methods were used to drive the south tunnel, which broke through in 2018, with TBM Kora deployed for the north tunnel. Cross passages between the two tunnel tubes are being driven at intervals of 500 m.
“We are extremely proud to be part of this once-in-a-century project and to be able to demonstrate Porr’s expertise in civil engineering, infrastructure and tunnelling,” said Porr CEO Karl-Heinz Strauss. “The tunnel breakthrough is a key milestone and a special moment for everyone involved in the project.”
The tunnel forms part of a new railway that will enable people to travel between Graz and Klagenfurt in 45 minutes. The Koralm Railway is a key project in the Baltic-Adriatic Corridor and links up-and-coming economic areas on the Baltic Sea with the Adriatic region.