The role of assessments in highway bridge management

Highway structures represent a significant asset that forms an integral part of the UK transport infrastructure. The current programme for the assessment of the load-carrying capacity of virtually all highway bridges in the UK started with the publication of departmental standard BD21 in 1984. A large number of bridges have been assessed as sub-standard during the programme; that is, they have been shown to be theoretically incapable of carrying a 40 t vehicle or an 11·5 t axle load in accordance with the requirements of BD21. There are still a significant number of sub-standard bridges that remain to be strengthened and the potential cost to the UK economy is substantial. The application of a robust assessment regime using an appropriate level of analytical tools would ensure that this investment is well spent to maintain the safety of the highway, avoid disruption to customers and limit environmental impact. It is suggested that rather than the highway assessment programme drawing to a close after over 20 years there is now an important role for assessments in delivering consistent levels of safety and reliability across the network.