Brenner Base Tunnel

The Brenner Base Tunnel (BBT) is one of Europe’s most significant infrastructure projects. With a total length of 64 kilometres – including the Innsbruck railway bypass – the world’s longest underground railway link is being built between Innsbruck in Austria and Franzensfeste in Italy. As the centrepiece of the European Scan-Med Corridor, the Brenner Base Tunnel is paving the way for an efficient, sustainable and future-oriented transport link across the Alps.

Amberg Engineering has been involved in the construction of the Brenner Base Tunnel for many years and, in addition to providing overall project management for the three main construction lots (H21, H41 and H53), is responsible for key planning and management tasks in the two Austrian lots, H41 Sillschlucht–Pfons and H53 Pfons–Brenner. In both projects, Amberg is responsible for key areas of detailed design and, with its many years of experience in tunnel construction, contributes significantly to the projects’ success. Its services range from sub-project management of complex tunnel sections, through the management of the interior fit-out, to the overall management of the engineering consortium. In addition, Amberg is responsible for geotechnical site management and the coordination of numerous specialist disciplines and project stakeholders.

The H41 Sillschlucht–Pfons construction lot constitutes the northernmost tunnel section on Austrian territory. It comprises around 16 kilometres of twin-tube main tunnel driven by tunnel boring machine (TBM), a further 10 kilometres of conventionally driven tunnel (NATM), numerous cross-passages and shafts, as well as the interior fit-out of the Innsbruck emergency stop and other underground structures.

This is immediately followed by construction lot H53 Pfons–Brenner, which, with an investment volume of around one billion euros, represents the largest and, at the same time, the southernmost construction section of the Brenner Base Tunnel on the Austrian side. In addition to two main TBM tunnel tubes, each 7.6 kilometres long, this section comprises an approximately 9-kilometre-long exploration adit driven using conventional methods, the St. Jodok emergency stop and transfer point, cross-passages, shafts, an intermediate access point, and extensive facilities for materials management. The planning of these structures places the highest demands on the coordination of a wide variety of specialist disciplines and construction methods.

Particularly challenging in both construction lots are the varying geological conditions – including Innsbruck quartz phyllites, Grisons schists and Central Gneisses – thick overburden, and water inflows in the vicinity of tectonic fault zones. Added to this are the complex site logistics and the multitude of technical and organisational interfaces inherent in a major international project. Successful planning therefore requires a deep understanding of underground construction, as well as close cooperation between the client, designers and contractors.

With its many years’ experience in the design of complex tunnel structures, Amberg Engineering contributes its expertise throughout the entire project cycle – from design and planning for approval, through tender and construction planning, to geotechnical supervision of the construction works. Amberg Engineering’s involvement in construction lots H41 and H53 underscores the company’s international expertise in the realisation of challenging underground infrastructure and makes an important contribution to sustainable mobility in Europe.