With the awarding of the largest contract section on the Austrian side of the project, Pfons–Brenner, a significant step has been taken in accomplishing the longest underground rail link, the Brenner Base Tunnel (BBT). The Brenner Basistunnel Gesellschaft (BBT SE) commissioned the consortium comprising the Porr Bau GmbH, Hinteregger & Söhne Baugesellschaft m.b.H., Società Italiana per Condotte d`Acqua S.p.A. and Itinera S.p.A. The contract is worth around 966 million euros. A number of objections were lodged with the Austrian Federal Court of Administration prior to awarding the contract. However, they were turned down and the consortium headed by Porr confirmed as the best bidder.
More than 80 % of the BBT Construction Work awarded
The commissioning of this huge contract represents a further milestone for the BBT BE Austrian chair, Prof. Konrad Bergmeister; the project of the century has now reached its main construction phase: “More than 80 % of all construction activities for the Brenner Base Tunnel have been awarded. Its accomplishment represents a transport political necessity for developing the European rail corridor, which will above all, provide an advantage for forthcoming generations”.
The Pfons–Brenner Contract Section
The construction section constitutes the setting up of 37 km of main tunnel tubes between Pfons and the Brenner, some 9 km of exploratory headings as well as the emergency halt at St. Jodok. The two main tunnel tubes are to be excavated using tunnel boring machines. The other tunnel sections are to be built by drill+blast. Construction will take about six years.
Roughly four million cubic metres of excavated material will be handled in this contract section. At least a third of the excavated material in the Pfons–Brenner section can be reutilized to produce aggregate for in situ concrete, segments or filter gravel. The unsuitable muck will be carried directly by automatic belt conveyors to the biggest BBT dump facility in the Padastertal valley. No residential areas will be affected while the muck is being transported to the dump. Construction material will be carried either by train on the consortium’s own rail link from Steinach Station or from the Brenner motorway via the Saxen Tunnel directly to the construction site.
Brenner Base Tunnel – more than a Third of Driving accomplished
Construction work on the 64 km long Brenner Base Tunnel is forging ahead simultaneously at a number of sites and accesses both on the Austrian as well as the Italian side. By mid-March 2018 more than 80 km, in other words, more than a third of the 230 tunnel kilometres that have to be excavated, had been driven including 23 km of the main tunnel, 29 km of exploratory headings and approx. 28 km of access, rescue and logistics headings. At present, apart from the conversion and upgrading operations at Innsbruck and Franzensfeste stations, four tunnel construction sections are being excavated. In South Tyrol work is progressing 24/7 at the Eisack underpass to the north of Franzensfeste, the Mauls 2-3 lot (Mauls to Brenner) and in Tyrol at Wolf/Steinach at the Pfons–Brenner lot as well as in the Ahrental valley at the Tulfes–Pfons lot.
Key Data Brenner Base Tunnel
Length (incl. Innsbruck bypass),
Portal Tulfes to portal Franzensfeste: 64 km
Length, portal Innsbruck to portal Franzensfeste: 55 km
Max. rock overburden: 1800 m
Internal diameter: 8 m
Longitudinal gradient: 4.0–6.7 ‰
Design speed for goods traffic: 120 km/h
Design speed for passenger traffic: 250 km/h
Emergency halts: 3 (Innsbruck, St. Jodok, Trens)
Excavated material: 17 million m³
Excavation methods: 30 % drill+blast, 70 % TBM