Mühlhausen im Täle
Filstal Railway Viaduct
Mühlhausen im Täle, Germany / 12.2013 - 09.2023
Between the Albaufstieg tunnels and the upper Filstal valley, a structure has been built that defines the route of the new Wendlingen–Ulm line. Adjacent to the portals of the Boßler and Steinbühl tunnels, the Filstal Bridge spans the landscape of the upper Filstal valley and links the tunnels, the bridge and the tunnels to form a continuous section of the new high-speed line. As part of the ARGE EÜ Filstal Max Bögl/PORR consortium, PORR Ingenieurbau was responsible for the design and construction of the two railway viaducts as well as other structural engineering projects along this section of the line.
Facts & Figures
Company
ARGE EÜ Filstal PORR/Max Bögl
Type
Bridge construction
Runtime
12.2013 - 09.2023
Filstal Bridge as part of the new Wendlingen–Ulm railway line
Bridge between the Albaufstieg and the Filstal
The Filstal Bridge is situated on the new Wendlingen–Ulm line, which will form part of the high-speed rail link between Stuttgart and Ulm. At the transition from the Albaufstieg tunnels into the Filstal, the structure spans the A8 motorway, the River Fils, the L1200 road as well as other transport routes. As the track spacing within the tunnels is around 30 m, two separate bridges were constructed. The bridge in the direction of Ulm is 485 m long, whilst the structure in the direction of Stuttgart is 472 m long. With pier heights of up to 85 m, the two bridges dominate the valley between the tunnel portals and the mountain ranges of the Swabian Alb.
Two bridge structures for high-speed rail
The two superstructures were constructed as six-span prestressed concrete box girders. Each superstructure is approximately 8.40 m wide. The distinctive Y-shaped piers support the two bridge structures and form the defining design feature of the Filstal crossing. At the same time, they reduce the number of foundation points within the valley. In addition to the railway viaducts, other structures were built, such as portal canopies, plant buildings, fire-fighting water tanks, pumping stations, emergency access routes, stairways, retaining walls, as well as road and path connections.
Building between steep slopes and tunnel portals
The works took place in the immediate vicinity of the two Alba ascent tunnels. The construction sites were partly situated on slopes and in the vicinity of existing transport routes. Both pile-slab foundations and shallow foundations were used for the foundations. The northern abutments were additionally anchored into the slope. The structure was designed such that the columns and box-girder superstructure are largely monolithically connected to one another. The connection to the abutments is achieved via spring plates, whilst movable bearings were provided only at the portal of the Steinbühl Tunnel.
Section-by-section construction of the superstructure
An overhead advancing formwork system weighing around 800 t was used to construct the bridge superstructures. Steel auxiliary towers were also employed. The superstructures were built in ten concreting sections per carriageway. Step by step, the formwork, reinforcement and concreting were carried out before the force-fit connection between the superstructure and the pier struts was established. In this way, the two bridge structures grew together section by section above the valley.
The basis for the new line
Even before trains began crossing the Swabian Alb, the structures for crossing the Fil Valley were erected between the tunnel portals. With the railway viaducts, tunnel connections and accompanying civil engineering structures, a central section of the new Wendlingen–Ulm line was completed. Between the Albaufstieg, the tunnel and the valley, the Filstal Bridge connects the individual structures to form a continuous section of the line.