DYWIDAG Tendons for Germany’s largest Bascule Bridge: The new Hunte Bridge near Berne
Between the municipality of Berne and the town of Elsfleth in the Wesermarsch administrative district northwest of Bremen, a new bascule bridge was recently built over the Hunte River. The bascule bridge replaces a 1951 lift bridge located at a distance of approximately 20m from the new structure that no longer fulfilled today’s technical requirements.
The new bridge is part of the new construction of Federal Road No. 212 in Lower Saxony. Thanks to its clearance that is 1.90m higher than that of the old lift bridge, and thanks to its efficient lifting and lowering mechanism, it will significantly reduce wait times for traffic.
The new bascule bridge has a total length of 84m, making it the largest single-leaf bascule bridge in Germany. The western approach bridge has a length of approximately 60m, while the eastern approach is approximately 90m long. The superstructure of the bascule bridge consists of steel over a substructure of reinforced concrete. The bridge was designed with a shallow foundation and is supported by an abutment.
The open spans of the bridge measure 66.3m, and the structure has a design width of 14.65m. When the bridge is fully opened, the leaf reaches a height of 70m. The rear part of the bridge deck lowers itself into the foundation of the bridge pier during opening, serving as a counterweight. The 700t leaf of the bridge was positioned from the shore.
The 115t pivot bearing was assembled on site using a heavy-duty crane.
To post-tension the two approach bridges, DSI supplied 48t of Type SUSPA Systems, 19-0.62" Strand Tendons conforming to Z-13.1-129 approval.
Inside the mechanism, where the hydraulic power unit with pulling cylinders is located, 108 unbonded, 26mm, 32mm and 40mm Ø, WR, grade 950/1050 DYWIDAG 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 DYWIDAG Bar Tendons for the bascule bridge. The stressing of the 44, St 32 WR DYWIDAG Bar Tendons was carried out at a height of approximately 8m from below using a 110 MP Jack.