New railway “Unter­inntal­bahn”

The new railway “Unterinntalbahn” is part of the TEN priority project for the creation of a high-speed railway line between Berlin and Palermo. The supply line of the Brenner was extended with four lines using mining & open cut construction. The complex geological and hydrological conditions required a special building method.

The new railway as a relieve for the traffic

Due to the dense population and the strong increase in traffic in the Lower Inn Valley along the A12, a large part of the 40 km long first section will run in two tunnels: the Terfener Tunnel and the Munsterer Tunnel.

GC GROUP was involved from the beginning with planning and consulting services for the client Brenner Eisenbahn Gesellschaft (BEG) in 7 of the 10 main construction lots in the planning as well as in the construction supervision and geological documentation.

Challenging conditions

The tunneling work took place under difficult conditions, as on the one hand the overburden was very small and on the other hand the geological and hydrological conditions were very demanding.

There’s no such thing as impossible

For this reason you had to use a wide variety of methods. In addition to the planning of the mining method, a special mining method was successfully implemented using compressed air by means of a jet process. For the first time in this project, the cut & cover method of construction was carried out using the jet blasting method under compressed air conditions from the tunneling process. In one section, the water table was only a few meters below the surface, which required an open construction method with sealed construction pits.