Between the municipality of Berne and the town of Elsfleth in the Wesermarsch administrative district northwest of Bremen, a new bascule bridge was built over the Hunte River. The bascule bridge replaces a 1951 lift bridge located at a distance of about 20 m from the new structure that no longer fulfilled today's technical requirements.
The new Hunte Bridge is part of the new construction of Federal Road No. 212 in Lower Saxony. Thanks to its efficient lifting and lowering mechanism, it significantly reduces wait times for traffic. Its clearance that is 1.90 m higher than that of the old lift bridge also contributes to this improvement.
The new bascule bridge has a total length of 84 m, making it the largest single-leaf bascule bridge in Germany. The western approach bridge has a length of approx. 60 m, while the eastern approach is about 90 m long. The superstructure of the bridge consists of steel over a substructure of reinforced concrete. The bridge was designed with a shallow foundation and is supported by an abutment.
Leaf reaches height of 70 m
The open spans of the bridge measure 66.3 m, and the structure has a design width of 14.65 m. When the bridge is fully opened, the leaf reaches a height of 70 m. The rear part of the bridge deck lowers itself into the foundation of the bridge pier during opening, serving as a counterweight.
Leaf weighs 700 t
The 700 t leaf of the bridge was positioned from the shore. The 115 t pivot bearing was assembled on site using a heavy-duty crane. To post-tension the two approach bridges, DSI supplied 48 t of strand tendons conforming to Z-13.1-129 approval.
Inside the mechanism is the hydraulic power unit with pulling cylinders located. 108 unbonded WR bar tendons conforming to Z-13.72-50123 approval were installed to stabilize the bascule system with the bottom counterweight and the accessible rear assembly.
A unique feature of this project was the tensioning of the anchorages of the bar tendons for the bascule bridge. The stressing of the 44 bar tendons, St 32 WR, was carried out at a height of approx. 8 m from below using an 110 MP jack.