Detailed information

Initial design

The bridge was originally designed as a continuous, three-span steel-concrete composite structure with a concrete slab. The main structure consisted of four rolled HL 1000A girders in S355J2+M grade and steel crossbeams of HL 1000A in S355J2+M grade. The concrete slab connects to the load bearing structure with the use of shear studs.
 
Basic parameters:

• Road class Z (speeds of up to 60 km/h)
• Load class B according to PN-85 / S 10030
• Theoretical spans: 20.75 m x 18 m x 17.75 m
• Total width: 11.2 m
• Skew angle: 90 degrees

Design optimisation

As part of the design optimisation, a composite steel structure with the use of rolled profiles in the new S460J2W + M steel grade according to PN-EN 10025-5: 2019 was proposed. HEA 900 profiles were used, which allowed for weight reduction and an increase in bridge clearance. The S460J2W steel grade, dedicated to hot rolled profiles, is known as Arcorox® 460. This steel is characterised by a high yield strength of 460MPa and, characteristic of steel according to PN-EN 10025: 5, increased resistance to atmospheric corrosion.

The cross bracing elements have also been optimised – the welded steel cross beams at support and in span were replaced by concrete crossbeams for the end supports and intermediate pillars, without the need for span crossbeams. This design is in line with the Ministry of Infrastructure’s guidelines as set out in the ‘Directory for Typical Road Structures, Bridge Structures, and Culverts’ (Katalogu Typowych Konstrukcji Drogowych Obiektów Mostowych i Przepustów).

The next bridge reconstruction

A second bridge is under reconstruction in Poland using the Arcorox® 460 weathering steel solution as part of the ‘Giełczew River road bridge reconstruction on 2118L district road of Biskupice – Fajsławice’ investment project. Construction is set to start at the beginning of 2021.