As bridge design continues to evolve across Australia, access to practical, up-to-date technical guidance is essential. Two newly released resources aim to support engineers, designers, and decision-makers in delivering more efficient, durable, and cost-effective steel bridges.
Together, these guides provide end-to-end support across both preliminary concept planning and detailed design.
Developed by HERA (Heavy Engineering Research Association of New Zealand) in collaboration with BlueScope and industry partners, the updated Weathering Steel Design Guide for Bridges in Australia is now available.
This 2025 edition is a comprehensive update of the original 2017 guide, bringing together applied knowledge and new industry practices to support the design of economical bridges made from REDCOR® weathering steel.
It collates essential guidance to assist the Australian industry with the efficient and appropriate application of weathering steels in bridge projects. The guide also provides practical advice to help achieve the expected performance and planned design life of these structures in local conditions.
Supporting the design of efficient and durable bridges
Steel has long been a trusted material for bridge construction due to its high strength-to-weight ratio. This becomes increasingly important for longer spans, where lower dead load can lead to a more efficient structure and lower foundation costs.
REDCOR weathering steel offers an additional advantage: long-term durability. In suitable environments, a tightly adherent oxide layer or ‘patina’ develops, which significantly reduces the corrosion rate compared with conventional structural steel.
When used in an appropriate environment and detailed correctly, REDCOR weathering steel can deliver lower whole-of-life costs compared to conventional carbon steel and concrete bridges. It can provide an attractive, very low-maintenance and economical solution, extending the scope for cost-effective steel bridges.
This new guide helps stakeholders make the most of those benefits by providing technical guidance tailored to the Australian context. It covers key considerations across design, detailing, fabrication, construction, inspection, maintenance and rehabilitation.
“We’re seeing growing interest in the use of weathering steel for bridge projects across Australia,” said Rob Danis, BEng (Civil), National Business Development Lead – Infrastructure, BlueScope.
“This guide is about giving engineers the confidence and tools to design for durability, and to fully realise the performance and economic benefits REDCOR weathering steel can offer when used in the right conditions.”
In support of broader bridge design initiatives, a second key resource has also been released: the Technical Guide: Composite Steel Road Bridges, developed by experienced bridge designers from the engineering firm WSP in collaboration with BlueScope.
This highly visual and comprehensive guide supports the preliminary design of economical composite steel multi-girder road bridges. Aligning with current Australian standards, the guide assists civil engineers, government departments, construction managers, quantity surveyors and procurement professionals with early-stage planning and design.
Highly visual format
What sets this resource apart is its clear, image-led format, featuring striking photography of steel bridges from Australia and around the world. The guide presents span tables and example configurations in a clear and easy-to-follow layout, enabling project teams to quickly assess the suitability of steel within bridge design while referencing real-world examples.
“This guide gives engineers a fast and reliable way to assess whether a steel bridge solution is viable for their project,” said Danis. “It enables informed planning based on up-to-date Australian standards, backed by global best practice and local experience.”
BlueScope manufactures a range of flat and welded steel products made from REDCOR weathering steel, including plate as well as welded beams and columns. These products are used across a variety of bridge types, from short-span to long-span road bridges, as well as rail and pedestrian bridges. BlueScope also offers XLERPLATE steel and welded beams made from both REDCOR weathering steel and XLERPLATE steel, suitable for diverse applications.
REDCOR weathering steel girder bridges are a compelling choice for modern bridge design. When correctly detailed, the excellent durability of REDCOR weathering steel can reduce maintenance requirements, resulting in cost savings over the bridge’s lifespan.
Industry knowledge and collaboration
This new guide replaces the original 1998 Composite Steel Road Bridges – Concepts and Design Charts published by BHP Integrated Steel. It incorporates more than two decades of acquired industry knowledge and evolving construction practices and reflects the latest Australian Bridge Design Code (AS/NZS 5100.6:2024).
The included charts provide a practical resource for the early-stage design of composite steel bridges with spans of up to 80 m. They include both standard BlueScope Welded Beams and custom-made three-plate or box girders for longer spans, with options for REDCOR weathering steel and painted XLERPLATE steel.
This publication is intended as a starting point for fast, preliminary bridge design. While it offers a robust foundation for assessing feasibility, a qualified engineer must be engaged for detailed design and final validation.
“By making early-stage steel bridge design more accessible and visual, we hope this guide becomes a go-to reference for project teams across Australia,” added Rob Danis. “It’s a resource that allows for smarter planning and better conversations around cost, buildability and timing.”
Both of these updated resources – The 2025 HERA Design Guide for Weathering Steel Bridges and the Technical Guide: Composite Steel Road Bridges – highlight the importance of industry collaboration.
They reflect the combined expertise and input of engineers, fabricators, civil construction companies, government departments, and other key stakeholders across the bridge design and construction sector.
View the bride guides here.
