Excavation has begun on the Gardena Tunnel, part of the Brenner Base Tunnel project.
TBM Kathrin has started boring the Fortezza-Ponte Gardena lot in Trento Alto Adige.
The launch of the TBM follows the completion of the 650m-long Funes exploratory tunnel that provides access to the mountain massif. From here, the 144m-long TBM, with a cutterhead of nearly 10m diameter, will excavate the twin tubes of the Gardena Tunnel and the interconnection tunnels with the future Ponte Gardena station.
This lot includes the excavation of more than 16km of tunnels and the installation of approximately 9,000 precast concrete segments.
The RFI (FS Italiane Group) project is being delivered by Webuild, in consortium with Implenia and SELI Overseas.
The Fortezza-Ponte Gardena lot is the first section of the quadrupling of the southern access of the Munich-Verona route. The Brenner Base Tunnel connecting Innsbruck in Austria and Fortezza in Italy is almost entirely underground, with 52km of tunnels designed to reduce gradients compared to the existing line, increase train speeds and boost freight transport capacity.
TBM Kathrin is a dual mode machine, capable of operating in hard rock and unstable ground. It recently completed the undercrossing of the Brenner highway.
The machine’s efficient motors and cooling water recovery systems reduce energy consumption by 20-25% compared with traditional TBMs, Webuild says.
Work is also progressing on other fronts. At the Forch cavern, preparations are under way to excavate the 15km Scaleres Tunnel, while at the Chiusa access adit, 1.4km of the planned 1.8km have been completed. Activities involve geologists and operations teams working simultaneously at multiple sites, including tunnels and a 250m viaduct over the Isarco River and upgrades to the Ponte Gardena station.
Once completed, the 64km-long BBT will be the world’s longest underground railway tunnel. With slopes of only 4-7%, it runs 580m below the Brenner Pass. The tunnel will reduce the Fortezza–Innsbruck line by 20km.
