NEWS

Breakthroughs are a special moment in tunnelling work. For the Brenner Base Tunnel project, this joyous breakthrough event took place on 17 September in the Sill Gorge. To the cheers of the miners, the first main tunnel breakthrough in the Austrian project area took place at 13:30 using excavators and mechanical chisels.
As part of the "H41 Sill Gorge - Pfons" construction lot, the miners have excavated around 2.4 km of the main east tunnel northwards in the direction of Innsbruck, using the classic drill and blast method. This tunnel section is now connected to the "H21 Sill Gorge" construction lot.

BBT SE CEOs, Martin Gradnitzer and Gilberto Cardola: "Today marks another important step in the Brenner Base Tunnel project. Work is proceeding apace on all construction sites in both Italy and Austria. Our special thanks therefore go to the miners and engineers who are driving the tunnel a little further every day." The breakthrough ceremony began with a minute's silence in memory of the surveyor who was killed in an accident in March.

Rene Zumtobel, Provincial Councillor for Transport and the Environment: "With today's breakthrough, the provincial capital, and thus Innsbruck's main railway station as the most important mobility hub in western Austria, will be connected to the Brenner Base Tunnel. The many tunnel breakthroughs along the 64-kilometre underground route represent a single great breakthrough for European rail transport as well as a massive reduction in traffic for the population and the environment in the future. This brings us another step closer to halving the journey time from Innsbruck to Bolzano."

Other guests were present at this festive occasion, including the tunnel patroness of the "H21 Sillschlucht" construction lot, Katharina Willi, as well as her husband and 1st Deputy Mayor of Innsbruck, Georg Willi, and other representatives of the construction companies.

The ceremony took place in the 130-metre long east main tunnel within the Viller Berg. This section of the tunnel includes the northern main portal of the Brenner Base Tunnel. Passenger trains from Innsbruck main station travelling to Italy will run through this east main tunnel.

The Brenner Base Tunnel is a tunnel system with a total of more than 220 kilometres of tunnels, of which 178 kilometres have already been completed.
In addition to the two main tunnels for railway traffic, the system also includes evacuation tunnels, access tunnels, safety tunnels and cross passages.

Facts and figures about the Main East Tunnel

Since mid-January 2022, the works on this lot have been carried out by the consortium "ARGE BBT construction lot H41 Sillschlucht-Pfons", which consists of the companies Implenia Österreich GmbH, Implenia Schweiz AG, Webuild S.p.A. and CSC costruzioni sa. These works are expected to last until summer 2028; the contract sum amounts to about 651 million Euro.

Excavation work in the east tunnel began at the end of March 2023. Blasting work started from Ahrental and moved in the direction of Innsbruck up to the neighbouring construction lot "H21 Sill Gorge". The works on the "H41 Sill Gorge - Pfons" construction lot are on schedule.

Excavation length: around 2,350 metres
First volley: 31. March 2023 (for conventional tunnelling, this is the length of a blast, usually 1 to 1.70 metres per blast)
Tunnel spoil: approx. 156,000 m³ of rock
Required steel in tonnes: approx. 825 t of steel
Application of shotcrete in m³: approx. 14,100 m³
Quantity of explosives required for tunnelling: A total of around 350,000 kg of explosives, approx. 250 kg per blast Up to four blasts were carried out daily.
Shift operations / night blasting ban: The main tunnel tube was driven in shifts, usually three shifts of 8 hours each per day. Blasting was carried out between 6 a.m. and 10 p.m., meaning that no night blasting took place out of consideration for the residents in the area.

Breakthrough of the main west tunnel in spring 2025

Tunnelling on the west tunnel began in November 2022. This stretch of main tunnel is around 3,400 metres long and the breakthrough in the Sill Gorge is planned for spring 2025.