Vienna Metro Expansion
U2xU5
Vienna, Austria
35 meters below Vienna: Doka delivers custom-engineered tunnel formwork for major metro expansion
Where tunnel tubes meet at different angles, the project requires systems precisely matched to geometry, construction sequence and logistics. With the extension of metro line U2 and the construction of U5, Vienna’s first fully automated metro line, Wiener Linien is expanding capacity for future urban mobility.
Doka supports this mega project with its comprehensive engineering and execution expertise—from 3D planning and pre-assembled formwork units to precise on-site assembly. Thanks to modular systems, many components can be reused multiple times and across different construction phases, ensuring a reliable and predictable construction process—even under demanding underground conditions.
Building type
Tunnel and station structures
Challenge
Complex geometries and intersections in inner-city metro construction
Limited space and complex logistical constraints – both underground and above ground
Solution
3D model based planning and individually tailored formwork solutions enable precise representation and execution of complex transition areas, minimizing the need for rework on site.
A modular logistics and formwork concept featuring pre-assembled units and a piggyback transport arrangement on transfer carts enables efficient material handling and a smooth workflow.
Precision in complex tunnel geometries
Complex tunnel geometries require tailor-made solutions. In inner-city metro construction, Doka delivers precise transitions – from skewed intersections, executed with specially adapted segments and additional intersection formwork travellers, to widening sections where tunnel tubes merge into a single structure.
Inclined escalator tunnels can also be constructed with high precision using flexible, foldable formwork solutions. The segments are assembled in a horizontally in a compact, folded position, moved into the required inclination, connected and then unfolded to their final cross-sectional size.
Hans Eder | Senior Project Engineer | Doka Austria
„The U2xU5 metro expansion brings together a highly specialized project team from engineering, structural design, pre-assembly service, and logistics, working in close coordination—often in parallel on a wide range of structrual elements with different technical requirements and construction sequences. The key challenge lies in coordinating all interfaces to ensure that planning, pre-assembly, and execution fit together seamlessly. One particular highlight for me is the exceptional level of collaboration between all parties involved. Seeing so many people working hand in hand once again demonstrates how important a shared goal is for the success of a project.“
Efficient logistics both underground and above ground
A specially developed transport-wagon concept is used to meet the logistical challenges of underground construction: formwork traveller segments are assembled on transport wagons, transported underground and connected on site as required. This allows variable formwork travellers to be configured flexibly for different concreting lengths.
Once a construction section is completed, the segments are dismantled, transported to the next location and reconfigured. This modular approach ensures a continuous and efficient material flow, enabling optimal use of restricted space and allowing different elevation levels to be balanced effectively throughout the construction process. Delivering such tailor-made solutions for complex infrastructure projects reflects a principle deeply rooted at Doka: what is extraordinary for others is standard for us.
Project data
Year of Completion
2030
Project Duration
2021–2030
Country
Austria
City
Vienna
Client
Wiener Linien
Contractor
ARGE U2 17–21 (STRABAG and PORR)