Erdinger Ringschluss: Extension of the railway tunnel at Munich Airport

The PORR GmbH & Co. KGaA / PORR Bau GmbH consortium extended the existing railway tunnel to Munich Airport, which terminates at the level of the Terminal 2 satellite to the east, to allow suburban rail and other trains to pass through the airport. The section, which consists of an approximately 1,555m long tunnel and an approximately 306m long ramp structure, is a milestone for the Erdinger Ringschluss circular rail link. September 2018 saw the groundbreaking ceremony for the tunnel extension, and PORR completed the structural work on schedule in June 2021.

The Erdinger Ringschluss is approximately 26km long and consists of 3 construction stages: the Neufahrner Kurve, which was completed in 2018, the Lückenschluss Erding and the Walpertskirchener Spange. It represents an important link for suburban public transport north of Munich and connects the airport to the rail networks of northeast and southeast Bavaria.

A complex project on a tight schedule
Part of the tunnel structure was built using open-cut tunnelling and part using the cut-and-cover method. The works included three emergency exits and nine culvert structures, as well as the dismantling, restoration and technical fit-out of roughly 10,000m² of aircraft operation areas.

Watch our video about the project in Vimeo:  PORR Germany . Erdinger Ringschluss: Extension of the railway tunnel at Munich Airport on Vimeo

Some 50,000m² of diaphragm walls, 80cm to 100cm wide and up to 20m deep, were constructed for the excavation pit. Underwater concrete floor slabs with a thickness of 1.40m were laid in the 18 excavation docks of the tunnel to seal off the bottom of the construction pit. A total of 8,000m² of sheet piling had to be constructed to secure the construction pit for the 306m-long ramp.

The exceptionally tight schedule posed a particular challenge for all the PORR companies involved. First of all, around 250m of tunnel was built in the eastern runway area of the satellite terminal. Starting from the date the runway was closed, only nine months of construction time were available to build the tunnel and completely reopen the runway. The cross-company cooperation with PORR Spezialtiefbau, the Pile Driving department and the Dewatering department has once again resulted in a virtually defect-free precision landing in this technically very challenging project.

To the PORR Video Neubau des S-Bahntunnels "Erdinger Ringschluss" am Münchner Flughafen