The Department for Transport has unveiled the road condition categories set to be brought in under a new condition monitoring standard due out next year.
A first iteration of PAS1261 is currently with the DfT for review following the initial results of a road condition monitoring study carried out by TRL, which benchmarked new monitoring technologies against visual inspections.
The new standard aims to open up condition reporting to a wide range of largely automated technologies rather than the current obligation for local authorities to use SCANNER to report the condition of all classified local roads to DfT.
It will be possible for SCANNER to still be used once the new standard comes in, as well as visual inspections and technology including mobile phone and dashcam technology, dedicated survey vehicles and crowdsourcing from telematics and from apps.
Speaking at the Strictly Highways conference, a TRL representative outlined the thinking behind the new condition categories, which will take over from the red, amber, green levels to indicate the state of the network.
He said: 'With different technologies measuring different things a defect catalogue is not practical. It leads to "implied" data collection methods excluding some technology and requires a ruleset to obtain categories, which stifles innovation.
'A consensus was agreed on an "end result" approach to PAS2161, which would categorise the treatment required to restore this sub-section to good/as new condition.'
The PAS will define five new condition categories:
1 No deterioration - Pavement would not be considered for maintenance
2 Minor (and/or aesthetic) deterioration - Light touch maintenance (eg minor patching)
3 Moderate Deterioriation - Localised intervention or mid-life preventative maintenance (e.g. surface dressing, patching, crack sealing patching of anti-skid surface)
4 Moderate to Severe Deterioration - Preventative maintenance perhaps full carriageway (eg resurfacing with thin overlay/surface dressing, multiple patching, edge haunching, renewal of anti-skid surface
5 Severe Deterioration - Substantial maintenance is required which is likely to include full carriageway resurfacing and reconstruction
TRL also revealed some early insights from the results of the road condition monitoring study, which involved engineers' inspections as an independent benchmark for the data.
The engineers came from Bristol, Derby, Doncaster, Hertfordshire, Reading and Surrey councils and their analysis was compared to survey techniques from RoadMetrics, Metricell, WDM, PTS, Xais, NIRA dynamics, Cyclomedia, Vaisala, Gaist, Waterman and RoadBotics.
TRL developed an app to allow engineers to record their ratings on a tablet. The co-ordinates recorded with each rating enabled them to be fitted to the network. These were resampled to provide category ratings for each 100m length.
The study found that where there was data available, the technologies were 'highly self-consistent' with good repeatability of the data from a number of devices.
There was also an indication that some monitoring devices are ‘more likely to report higher or lower’ conditions consistently.
The evidence found that agreement over the percentage in each category across the fleet is not yet strong, however. Differences were found between the fleet of new technologies and the benchmark analysis, and between the different technologies.
'There is now a need for collaboration on fleet consistency to identify where refinements to the process can be achieved,' the TRL representative said.
'At this point in the study, the fleet agrees with itself slightly less than eight engineers did: 60% of our engineers provided identical ratings for 50% of the network but this was less than 50% for the road condition monitoring data.
'There is a need for further discussion and development of cross-fleet consistency. We will be working with the industry on this as the study continues.'