Aluminium in bridges
How do you choose the right aluminium bridge decking for your next project? We offer support on isotropic and orthotropic deck solutions that reduce weight, speed up installation, and minimize maintenance compared to steel and concrete. Below, you will learn more about aluminium in bridges, technologies, use cases and more.
Aluminium bridge decking technologies
We offer support on two aluminium bridge decking technologies:
Isotropic decks
- Definition: Uniform plate-like aluminium deck with consistent properties in all directions.
- When to use: Short to medium span bridges and rapid replacement projects.
- Applications: Urban bridges, pedestrian/cycle bridges, and modular rehabilitation.
- Surfacing: Compatible with waterproof membranes and asphalt or resin based overlays.
- Pre-assembly: Supplied as prefabricated panels for rapid installation.
- Maintenance: Minimal corrosion risk; straightforward inspection and replacement.
Orthotropic decks
- Definition: Stiffened aluminium plate with longitudinal/transverse ribs for high stiffness to weight.
- When to use: Spans requiring higher stiffness and lower self weight compared to concrete/steel decks.
- Applications: Highway bridges, movable bridges, and weight restricted structures.
- Surfacing: Works with thin lightweight surfacing systems to preserve weight savings.
- Pre-assembly: Panelized with integrated stiffeners for efficient onsite handling.
- Maintenance: Durable against de-icing salts and marine environments.
The two bridge technologies have been successfully tried and tested on bridge deck projects for decades, and evaluations funded by the U.S. Federal Highway Administration show that aluminium decking is viable for many bridge applications.
Why aluminium is a great choice for bridges
Compared to materials like steel and concrete, aluminium bridge technologies offer a strong alternative because they make rehabilitation faster and less disruptive, especially with panelized, pre-assembled decks that allow short closures and staged installation.
Their low self weight preserves existing substructures and can even make it feasible to widen older bridges without major foundation work. Aluminium also stands up well in tough environments, de-icing salts, coastal air, and industrial atmospheres, which cuts corrosion risk and reduces maintenance needs.
Fewer repairs and easier panel replacement translate into lower lifecycle costs than steel or concrete, and the material supports sustainability thanks to high recycled content potential and full recyclability.
From oil platform to bridge
In October 2025, The Norwegian Public Roads Administration opened “Hangarbrua,” a 55 meter by 9-meter network arch pedestrian and cycle bridge built by Leirvik with Hydro and partners. Made entirely from recycled aluminium taken from the decommissioned Gyda oil platform, the 60 tonne structure was assembled off site and lifted into place over the railway at Leangen station in a single operation, showing how low weight can simplify installation.
A life cycle assessment by COWI found that using recycled post-consumer aluminium reduced CO₂e emissions by about 70% versus a stainless steel alternative, including end of life recycling potential. Hydro produced new extruded profiles from the recycled metal, some joined with friction stir welding and the bridge’s corrosion resistance supports minimal maintenance over time. Hangarbrua now forms a key link in Trondheim’s walk and bicycle route, improving connectivity while demonstrating circular construction in practice.
FAQs about aluminium in bridges
Isotropic decks use a uniform plate for consistent properties, while orthotropic decks add stiffeners to raise stiffness to weight for demanding spans.
Aluminium reduces self weight, speeds installation and resists corrosion, lowering maintenance compared to traditional materials.
Yes. Prefabricated panels support staged, night or weekend work with minimal traffic disruption.
Waterproof membranes with asphalt or resin overlays are commonly used, with anti-skid treatments as needed.
Yes. Aluminium is infinitely recyclable and supports circular project goals.
Apply regional bridge design codes and project specific testing/certification. Feel free to contact us for guidance.
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