Inspection of bridge road railing

Corrosion testing for alternative protection of railings

Sweden’s national road network has 16,018 bridges. Maintenance due to corrosion on bridge railings amount to large costs each year. Swerea has presented a study on railing protection using polyurethane and polyester filter fabric.

Maintenance and refurbishment of corroded bridge railing posts costs large sums each year. The most common method of renovation is time-consuming, costly and places restrictions on traffic users due to road closures.

On assignment from the Swedish Transport Administration, Swerea conducted an independent study to compare existing bridge railing materials with alternatives that require less maintenance. On two bridges near the Öland Bridge a new way of preventing corrosion on railing posts has been tested.

Elastic sock prevents corrosion

A polymeric material has been mounted around the railing post. This elastic material is fastened tightly to the railing post using special tools. Inside the “elastic sock” a surface that is similar to that of a fleece pullover is treated with a type of grease that prevents rust. The grease contains an anti-corrosion additive.

“The study shows that, after two years, the railing posts are still free of corrosion. We foresee a range of applications in areas where corrosion can pose a potential threat to safety, for example, pipelines and structures for barns or stables,” says Bror Sederholm, research project manager at Swerea.

Less maintenance and increased road safety

“We have strict design requirements when it comes to materials and construction methods. Our ambition is to make maintenance more cost-effective and to minimize traffic disruptions. The independent study by Swerea is a valuable basis for decisions on alternative maintenance measures for bridge railings,” says Adriano Maglica, bridges manager with the Swedish Transport Administration.