THE CONSTRUCTION LOT IN FIGURES
excavated tunnel sections
Approximately 6 km of main tunnel were constructed.
Construction of an approximately 9.7 km long rescue tunnel with a cross-section of approximately 35 m2.
Approximately 16.7 km of the exploratory tunnel were excavated northwards.
Executive construction consortium: Strabag SE / Webuild S.p.A. (formerly Salini-Impregilo)
Contract value: 377 million EUR
COMPLETED
All construction and tunnelling work on this construction lot was completed in May 2022.
EXCAVATION DATA
- Excavation 9.700 m
- Length 9.700 m
- Cross-section 35 m²
- Excavation 5.960 m
- Length 5.960 m
- Cross-section 70 m²
- Excavation 5.246 m
- Length 5.746 m
- Cross-section 70 m²
- Excavation 6.840 m
- Lenght 6.840 m
- Cross-section 115 m²
- Excavation 16.627 m
- Length 16.627 m
- Cross-section 49 m²
COMPLETED WORK
- Construction of a 9.7 km long rescue tunnel parallel to the Innsbruck railway bypass, which has been in existence since 1994, and two connecting tunnels between the BBT and this bypass
- Excavation of 16.5 km of exploratory tunnels between Ahrental and Schmirn for preliminary exploration of the rock mass
- Excavation of the Innsbruck emergency stop
- Construction of the main tunnel sections and cross passages for this construction lot
EXCAVATION METHODS
Two tunnelling methods were used in this construction lot.
The main tunnel sections east and west, the rescue tunnel running parallel to the existing Innsbruck railway bypass and the connecting tunnel between the bypass and the Brenner Base Tunnel were excavated using conventional blasting. In the area of the St. Jodok emergency stop, the two main tunnel tubes will be driven with a slightly larger cross-section in order to offer better chances of rescue.
The approximately 16.6 km long section of the exploratory tunnel in this construction lot, on the other hand, was excavated mechanically, i.e. with a tunnel boring machine (TBM). From September 2015 to July 2020, the 200 m long gripper tunnel boring machine (TBM) named Günther worked its way southwards from the Ahrental hub through the rock to the municipality of Schmirn. Since the breakthrough, this construction lot has been connected to the Pfons-Brenner lot.
PECULIARITIES OF THE CONSTRUCTION LOT
Intersection-free cross-over of the two connecting tunnels
The eastern (approx. 3 km) and western (approx. 4.2 km) connecting tunnels, which were constructed between mid-2015 and mid-2017, link the Brenner Base Tunnel with the Innsbruck bypass tunnel, also known as the ‘Inntal Tunnel’, which was put into operation in 1994.
The connecting tunnels are linked to the Inntal Tunnel in the Aldrans area. A 300-metre-long interconnecting tunnel to the Brenner Base Tunnel had already been already built during the construction of the Inntal Tunnel.
The two connecting tunnels cross over each other in the Lanser See area. This crossover is necessary to ensure a intersection-free transition from the Italian rail network (left-hand traffic) to the Austrian rail network (right-hand traffic) – and vice versa. North of the Innsbruck emergency stop, the two connecting tunnels lead into the Brenner Base Tunnel via the so-called junction chambers.