UK Roads Liaison Group

SCANNER RCI thresholds and weightings

The Road Performance Management Group identified the need for a further working group to review the operation of the SCANNER RCI on principal roads and develop the thresholds and weightings for use on other classified roads (B and C roads) and on unclassified roads in England, Scotland and Wales.

The Roads Board set up the SCANNER RCI Working Group with representatives from the Road Performance Management Group (RPMG), the SCANNER Project Management Group (PMG) and the UKPMS Steering Group (UKPMS SG)

The Group commissioned a further study to carry out a detailed investigation of the suitability of the thresholds and weightings proposed for the parameters measured by SCANNER surveys based on a detailed analysis of selected SCANNER data from an extensive but selective sample of sites and the development of some simple theoretical models and analysis methods.

This research is being conducted by TRL Ltd.  It is scheduled for completion by March 2007.

The detailed tasks include:

  • Investigating the overall SCANNER RCI results on principal and on other classified roads, comparing them between different types of local authority in England and Scotland, and recommending benchmarks for the different categories of local authority.
  • Investigating the differences in the RCI on principal and other classified roads between different types of local authority in England and in Scotland, investigating the sensitivity of the results to the different parameters, and recommending whether any changes in the method, groupings, combinations, thresholds or weightings are necessary or would be appropriate.
  • Testing the current proposals for the SCANNER RCI on unclassified roads in Scotland and England, reviewing and developing the method, groupings, combinations, thresholds, weightings and reliability and relevance factors currently proposed and providing evidence and justification for the values.
  • Investigating the current SCANNER RCI reliability factors.
  • Investigating the setting of targets and trajectories for the condition of local roads.
  • Investigating the inclusion of the new parameters for edge condition and transverse profile as part of the overall SCANNER RCI.