The Polish WKS Duna Polska, a member of the Duna Group, boasts significant experience in manufacturing and assembling steel structures on-site, particularly bridge structures. However, the construction of the Saupstadbrua Bridge in the outskirts of Trondheim, Norway, presented new challenges for the company.

The Saupstadbrua Bridge project comprised eight massive elements, each measuring 24 meters in length, nearly 6 meters in width, and over 3 meters in height, with each element weighing over 50 tons. During production, not only did the elements need to comply with European steel structure standards, but they also had to meet the requirements of the Norwegian Handbook R762! The bridge structure consisted of a large, rigid, closed box girder and two side cantilevers, which were produced as separate units and assembled in the final phase. Maintaining geometric tolerances for such large elements posed a significant challenge, necessitating meticulous and targeted planning before production. Strict assembly and welding instructions were developed to ensure optimal heat distribution during welding and to meet manufacturing tolerance requirements upon completion of the welding process.

Implementing corrosion protection to meet specific North European requirements presented new tasks. The different surfaces of the bridge were covered with three distinct painting systems. To begin the metal spraying process, a highly clean Sa3 surface with exceptional roughness of Ry5=85-130um had to be achieved. For this purpose, a very hard 700HV GH25/18 size fractured steel shot, specifically chosen for this project, was used. The production and painting processes were carried out according to strict specifications, under the technical supervision of the client, ensuring that each element met the very high quality standards.

For WKS Duna Polska, part of the Duna Group, the production and on-site assembly of the Saupstadbrua Bridge was not only a challenge but also an opportunity to demonstrate their expertise and commitment to quality! The successful completion of the project attests to the company's professionalism and innovative solutions in the field of steel structures.

Norwegian media coverage of the bridge structure on pages 132-143:

https://www.samferdselinfra.no/bladarkiv/samferdsel-infrastruktur-01-utgave-2024/