Tower cranes that rise more than 320 feet above a valley floor in Germany are being used to build a multi-span cable-stayed bridge that will relieve the small town of Horb am Neckar from heavy traffic. Originally slated for completion in 2026, an accident during a large-scale concrete placement will likely affect the schedule for the project, about 30 miles southwest of Stuttgart.
The 2,188-foot-long structure is being built by Porr Group, an Austria-based contractor ranked 63rd on ENR’s current list of prime contractors. It has a $125 million design-build contract awarded at the end of 2022 by the owner, the Karlsruhe Regional Council.
Locally based Leonhardt, Andrä und Partner is the designer for the contractor, having carried out studies and supported the owner in the procurement of the project between 2016 and 2021.
The cantilever girder bridge will have six spans, ranging from about 197 feet to 518 feet, crossing up to 230 feet above the Neckar River valley floor. Three central piers will rise in V-profiled pylons up to 295 feet, from which tin cables will radiate downward to support the continuous beams of the concrete deck.
The bridge would relieve the small town of Horb am Neckar, near Stuttgart, from heavy traffic. Representation courtesy of V-KON.media GmbH Trier
In February, several bolts failed in the formwork and formwork used to cast a pier crossbar due to “material defects,” according to the owner. No injuries were reported. The affected crossbar has since been replaced, while the likely contractual impacts are under review, the owner notes.
Meanwhile, the contractor has deployed two 316-foot and 331-foot-tall tower cranes to service construction crews. Having such high free towers is not normally possible, according to supplier Wolffkran. Tying them to the bridge would have been “disproportionately complex and expensive”.
