Tunnels are important traffic and civil engineering structures with high safety standards and demanding technical equipment.
Often the failure to meet these safety standards is the reason for refurbishment. In tunnel refurbishment, the main focus is on general repair, improvement of fire protection (in accordance with the German guidelines for road tunnel equipment and operation RABT 2006 - Brandschutz im Tunnelwesen - fire protection in tunnels), coating of internal walls to improve light reflection and facilitate maintenance, technical equipment and road surfaces.
The activities of the Tunnelling Division also include the widening of existing tunnels and the installation of new inner linings.
The Roppen tunnel between Innsbruck and Landeck in Austria was made safer by the construction of the second tube. The 5,069 meter long tunnel was driven conventionally.
Rehabilitation of the head race tunnel with downstream access tunnel and bypass tunnel