THE CONSTRUCTION LOT IN FIGURES
Tunnel tubes will be excavated in this construction lot
In total, approx. 22.5 km of main tunnel tubes will be excavated
Connecting tunnels to be constructed between the two main tubes
Tunnel boring machines of this construction lot: IDA and LILIA
Executive construction consortium: ARGE H41 Sill Gorge-Pfons consortium, consisting of Implenia Österreich GmbH, Implenia Schweiz AG, Webuild S.p.A, csc costruzioni sa
Contract value: 651 million EUR
CURRENT WORK
- Dismantling of the Lilia TBM
- Inner lining operations in the exploratory tunnel and main tunnel tubes as well as in the Innsbruck emergency stop
- Completion of the embankment of the Ahrental landfill
EXCAVATION DATA
- Excavation 11.303 m
- Length 16.594 m
- Cross-section 85 m²
- Excavation 258 m
- Length 258 m
- Cross-section 82-210 m²
- Excavation 5.246 m
- Length 5.746 m
- Cross-section 70 m²
- Excavation 1.316 m
- Length 2.260 m
- Cross-section 30-70 m²
- Excavation 702 m
- Length 702 m
- Cross-section 15-100 m²
COMPLETED WORK
- Installation of conveyor belt systems underground at the Ahrental landfill site and in the exploratory tunnel at the Padastertal landfill site
- Blasting excavation of the emergency stop, the west and east assembly caverns for the two TBMs, and the east and west main tunnels northwards (Innsbruck)
- Reinforcement works in the exploratory tunnel
- Installation of partition walls in the east and west Innsbruck connecting tunnels and a slab suitable for vehicle driving in the side corridors (‘safety corridor’)
- Installation of the long-distance pipe flushing system in the east and west Innsbruck connecting tunnels
- Construction of a production facility for the manufacture of tubbing rings on site at the Ahrental construction site
- Construction of a bridge over the A13 Brenner motorway.
- Mechanical excavation of the west (TBM Lilia) and east (TBM Ida) main tunnels southwards
EXCAVATION METHODS
Both tunnelling methods are being used in this construction lot: The main east and west tunnels northwards (towards Innsbruck) were constructed using traditional mining methods, i.e. blasting, while the two main tunnels southwards were constructed using machines, i.e. tunnel boring machines (TBMs).
Mechanical excavation began in 2023. On May 2nd, TBM Lilia set off on its 8,108 m journey in the main east tunnel. On June 27th, TBM Ida was started up in the main west tunnel. Both tunnel boring machines reached their destination in the second half of 2025.
SPECIAL FEATURES OF THE CONSTRUCTION LOT
NEW BRIDGE OVER THE A13 BRENNER MOTORWAY
Space is limited on the H41 construction site. In order to make optimum use of the available space and gain additional landfill space for the tunnel excavation material, the existing underpass to the A13 motorway exit towards Innsbruck was filled in and a prestressed concrete bridge was built over the motorway instead.
The possible construction times were specified by the motorway operator and were severely restricted by holiday periods and public holidays with high traffic volumes. Traffic restrictions were not permitted during these periods.
For the construction work, an assembly scaffold was erected above both lanes of the Brenner motorway; this work was carried out in 2023 over the space of 10 days during nightly total lane closures.
This allowed traffic to flow freely during the formwork and concreting work.
In the available construction period, which lasted only two months, the bridge structure was formed and concreted, and the assembly scaffolding was dismantled again. The bridge has been open to traffic and in operation since October 2023.