Sir, Your story on the Highways Agency's report on the repair of concrete on highway bridges said specialists had criticised the guide as 'outdated'. But it failed to give the Highways Agency's perspective, or that of the report's authors at TRL and the County Surveyors Society.
The guide was aimed primarily at younger engineers, although it was also considered to be of value to seasoned practitioners in concrete repair, due to the lack of published guidance.
The work was undertaken by extensive consultation and feedback, mainly from bridge owners. Inevitably, this had to take a backward look, to gauge experiences with different materials and techniques, whether good, bad or indifferent.
The intention was to learn lessons to incorporate into the guide. It was fully recognised that some repair materials had evolved over a period of time, but it is clearly difficult to assess their performance and durability until some time has elapsed.
To balance this approach, some of the latest research into concrete repair materials was included in the report.
Clearly, there is a need to update concrete repair specifications to achieve a consistent generic document that can be applied nationally. But it needs sufficient flexibility to deal with the many varied concrete repair applications, and align with the principles in the European standards and current best practice.
This is a significant aim and cannot be achieved quickly, particularly as it is important to work with the repair industry to ensure its relevance and suitability.
Neil Loudon, Senior technical adviser Highways Agency