By rosebell
The €60m contract for Brenner Base Tunnel Sill Gorge construction lot, which includes the northern portal, is officially completed by Porr within the 52-month timeline.
Although the stretch between the BBT’s northern end and the main station in Innsbruck is only 600m, it required some highly challenging engineering, that included inserting 60 anchor bolts, each 120m long, into the loose rock of the Viller Berg slopes at the northern portal.
Considering that the project has a close proximity to the Sill River and the narrow gorge, rhe works were also complicated above and below ground. Additionally, considering the nearby infrastructure, including the A12 Inntal and A13 Brenner highways, the Tirol Panorama Museum, the Untere Sill power plant and the ÖBB rail line in the Bergisel tunnel, was the other challenge of the construction team.
According to project manager Keinprecht: “The range of complex structures for the Sill Gorge lot was also challenging. We bored 170 pilings for the reinforced concrete retaining wall and built three 50m steel bridges, a 55m span bridge, a reinforced concrete pre-tunnel and the structure of the north portal itself. This goes to show the variety and complexity of the structures built as part of the lot.”
As an important feat of engineering, the construction of the two bridges over the Sill was done, while at the same time the recreational area in the Sill Gorge had to be preserved.
In order to restoring the construction site to its original state, the revegetation is undergoing and the two stretches of a hiking loop that run through the gorge will be reopened in spring next year.
Along with welcoming the completion of a further construction lot for what is due to be the world’s longest rail tunnel, BBT SE’s board directors Martin Gradnitzer and Gilberto Cardola stated: “The portals are clearly visible from the outside and these two north and south entrances to the BBT in Innsbruck and Fortezza will be the clear and unmistakable face of the Brenner Base Tunnel.”
