ABSTRACT
The UK procedure for assessing the structural condition of a road pavement includes the collection and analysis of deflection response to an impact load using a Falling Weight Deflectometer (FWD). There is a need to ensure that these devices are accurate and consistent. Initially in 1998, on behalf of Highways England, TRL introduced correlation trials to compare the levels measured by the devices on a range of test pavements under closely controlled conditions. More recently TRL have developed, with the involvement of the UK and Ireland FWD Group, a rigorous procedure which includes annual accreditation trials together with checking routines for both the contractor and the Auditor(appointed by Highways England) to apply. Within the standard for designing and maintaining the English strategic road network it is a requirement that survey data is collected using equipment that adheres to this procedure. This paper describes this procedure.
