Conventional steel bridges taking advantage of the latest advances in automated fabrication and construction techniques are able to provide economic solutions to the demands of safety, rapid construction, attractive appearance, shallow construction depth, minimal maintenance, and flexibility in future use. Weathering steel bridges have all these qualities, yet offer further benefits. Weathering steel bridges also have a good track record. A recent study by TRL indicates that weathering steel bridges built over the last 20 years are generally performing well. Where problems have been encountered, they have been the direct result of specific faults such as leaking deck joints, rather than any general inadequacy in corrosion performance.
Very low maintenance
Periodic inspection and cleaning should be the only maintenance required to ensure the bridge continues to perform satisfactorily. Hence, weathering steel bridges are ideal where access is difficult or dangerous, and where future disruption needs to be minimised.
Initial cost benefits
Cost savings from the elimination of the protective paint system outweigh the additional material costs. Typically, the costs of weathering steel bridges are approximately 5% lower than conventional painted steel alternatives. This was illustrated in a recent study on eight bridges in the UK. (Reference 4)
Whole life cost benefits
The minimal future maintenance requirements of weathering steel bridges greatly reduces both the direct costs of the maintenance operations, and the indirect costs of traffic delays or rail possessions, leading to major savings far in excess of the 5% on capital costs.
Speed of construction
Overall construction durations are reduced as both shop, and site painting operations are eliminated. Attractive appearance
The attractive appearance of mature weathering steel bridges often blends pleasingly with the environment, and improve with age.
The environmental problems associated with paint VOC emissions, and the disposal of blast cleaning debris from future maintenance work are avoided.
Health and safety issues relating to initial painting are avoided, and the risks associated with future maintenance are minimised.