• Start of tunnelling works on Vienna’s new U2 metro line
• Milestone with tunnelling start at Matzleinsdorfer Platz
• New Austrian Tunnelling Method in action

Vienna, 09.05.2022 – The consortium of Austria’s two largest construction companies, PORR and STRABAG, today achieved a new milestone in the City of Vienna’s biggest climate project together with the client, Wiener Linien: The first tunnelling works on the new U2 metro line began as planned at Matzleinsdorfer Platz. This marks the start of the largest single construction lot in the history of Vienna’s underground railway network.

PORR CEO Karl-Heinz Strauss: “We are applying our cumulative know-how in metro construction here. This project not only promotes sustainability after completion – we are protecting the environment even during the build phase. For example, we are using a tunnel boring machine powered by electricity for all five construction lots and we have significantly reduced traffic pollution”.

“This complex urban project also stands out for the way it challenges us across the board”, said Thomas Birtel, CEO of STRABAG SE. “It is not only the City of Vienna’s biggest climate-protection project, but also a team effort by three different construction disciplines. Together we are creating infrastructure that will leave a lasting mark on the city for decades to come”.

New Austrian Tunnelling Method in action

Both of the tunnel drives, each 4 km long, are being built with the New Austrian Tunnelling Method (NATM). Here, excavators dig forward metre by metre and secure the tunnel with shotcrete. Freezing boreholes were carried out prior to the work and ensure stability in the ground. In summer 2022, work will also begin on the other end of the new U2 tunnels in the Rathaus section.

Parallel to the tunnelling crew, the foundation engineering and structural engineering teams are working on expanding the shafts along the metro line so that tunnelling can progress without interruption.

Up to 500 staff on duty

At peak times, there will be up to 500 employees from STRABAG and PORR working on the project. The tunnelling teams will work around the clock in shifts to ensure that progress on the project is as fast as possible in this densely built-up, inner-city environment.

Once the tunnels in the vicinity of the new U2 stations are ready, the next phase will begin: work with the shield tunnelling machine, known as the ‘mole’. Set to start in 2024, the tunnel boring machine will dig the first sectional tunnel from Matzleinsdorfer Platz to Augustinplatz in the 7th district. This minimally invasive construction method will be used to build the tunnels between the stations in this section underground. The new U2 south branch to Matzleinsdorfer Platz is set for completion in 2028.