RELAXED GUIDELINES on dealing with road bridges which fail their safety assessments have been announced by the Highways Agency.
The new rules apply mainly to bridges assessed as substandard and in need of strengthening but which show no obvious signs of distress. They should cut the disruption caused by temporary safety measures such as propping and width restrictions.
Instead, engineers will be allowed simply to monitor the structures for up to two years before having to begin any strengthening work.
Agency bridge management project director Parag Das explained: 'We will be publishing the new rules in an advice note later this year. It has been eagerly awaited, especially by local authorities.'
Under Agency rules published last year, immediate action had to be taken when a bridge failed an assessment. At the very least this had to include propping or width and/or weight restriction as well as regular monitoring until strengthening was completed.
But cash-strapped local authorities have been struggling to comply with these requirements, and there has been considerable traffic disruption as a result of the restrictions imposed on some key bridges. Last year the Agency formed a national working group of all the major highway authorities in the UK plus specialist consultants, and the new advice note is the first result.
Public airing of the new rules was at a joint Agency/Institution of Civil Engineers conference on highways structures management this week. A paper was presented by working group member and secretary of the Standing Committee on Structural Safety Dr John Menzies, who said monitoring was also appropriate for substandard bridges likely to fail gradually.
This would exclude post-tensioned concrete bridges and those with inadequate shear reinforcement, where any failure could be sudden and catastrophic.