The first tunnel boring machine (TBM) for DB InfraGO’s major second main line project in Munich, Germany has been ordered, representing the start of the move to mechanised tunnelling.
The machine has been commissioned by the “Main Station Tunnel” consortium.
Deployment in Munich is planned from September 2026 to drive the around 3km exploratory and rescue tunnel between Donnersberger Bridge and Marienhof.
Overall project manager Kai Kruschinski-Wüst said: “With the order of the first tunnel boring machine for the exploratory and rescue tunnel, we are taking the next step in the major project of the second main line.
“The machine represents precision, teamwork, and progress – values that characterise our work on this future-oriented project. We are pleased that the machine is already under construction and will begin its work next year. Munich will thus gain a new lifeline for a sustainable transport infrastructure.”
The mixshield TBM, designed for Munich’s challenging ground conditions of clay, silt, sand and gravel, is being built by Herrenknecht at its Schwanau facility in Baden-Württemberg.
With a diameter of 5m, an overall length of 178m and a total weight of about 700t, the machine will pass beneath existing structures and infrastructure.
Following factory acceptance testing, it will be dismantled, transported to site in Munich, reassembled and prepared for launch.
Among the six TBMs to be used on the second main line, the first TBM for the traffic tunnels are scheduled to begin work in 2028.
Operating from the west and east, the TBMs will construct two traffic tunnels each as well as the exploratory and rescue tunnel, converging at Marienhof in the city centre.
This year, crews using conventional excavation finished the structural phase of a rescue shaft at Arnulfpark and a link tunnel at Marienhof.
The second main line is being constructed at depths reaching 48 metres between Laim and Leuchtenbergring.
The scope of work also includes the construction or refurbishment of five stations, upgrades to outer S‑Bahn branches, the introduction of new regional S‑Bahn lines and improved links to Munich Airport.
Completion is currently planned between 2035 and 2037.
