Brenner base tunnel

Planning for the longest underground railway connection in the world with a distance of 55 km

The Brenner Base Tunnel is the core element of the Brenner railway axis from Munich to Verona. The tunnel system consists of two single-track driving tubes, has an exploration and drainage tunnel and three emergency stops.

The project scope

The Brenner Base Tunnel consists of a system with two single-track tunnel tubes, which are connected with cross passages. The tunnel system includes a pilot tunnel, which is designed as a drainage tunnel or service tunnel. The tunnel system also includes three emergency stops for evacuating passengers in an emergency. These emergency stops also contain facilities for operation and maintenance work and are accessed from the surface through accessible access tunnels. Immediately north of the Innsbruck emergency stop, the two single-track connecting tunnels branch off into the existing Innsbruck bypass, so that the freight trains can bypass Innsbruck station underground in the south.

The geological conditions

The Brenner Base Tunnel runs through the entire central zone of the Eastern Alps through the so-called Tauern Window. The geology is largely based on schists and phyllites, also on gneiss and granites and only to a small extent on carbonates. When choosing the alignment of the main tunnel and the side accesses, the sometimes difficult geological and hydrogeological boundary conditions as well as construction, safety and economic requirements were examined and taken into account.

The implementation

The implementation of the base tunnel consists of several planning and construction lots – divided into exploration measures and main construction measures in Austria and Italy. In the course of the exploration measures, the side access tunnels and intermediate attacks as well as the excavation of the exploration and drainage tunnel are primarily carried out. In the course of the main construction work, the main tunnel tubes are being driven simultaneously from several intermediate points of attack. The main tunnels are driven either using tunnel boring machines (open TBM / shield machine) or conventionally by blasting.