Road accidents are a significant source of community costs associated with transport operations. More than a quarter of all wet-road accidents in the United Kingdom are related to skidding conditions, conditions which could be avoided if road surface conditions were monitored routinely and remedial treatment undertaken at high risk areas. Published evidence is briefly reviewed which relates measurement of skidding resistance and surface macrotexture depth with accident statistics; results obtained in London supplement this.
Equipment and techniques available to measure skidding resistance and surface texture are discussed critically, and equipment used currently in the United Kingdom to measure these parameters on a routine monitoring basis is described in detail. This equipment includes the laser-based High-Speed Texture Meter, capable of measuring texture depth at survey speeds of up to 100 km/h, the hand-held Texture Meter for checking resurfacing work in relation to specification texture depth requirements, and the Sideway-Force Coefficient Routine Investigation Machine now used to survey more than 80 000 lane km annually.
Finally, the paper describes measurements obtained with the various pieces of equipment, procedures for processing the results and, most importantly, current forms of results presentation which ensure that the maintenance engineer can easily make most effective use of the results. Emphasis is placed on use of visual summaries highlighting high-risk areas and computer-based research routines to list automatically details of the measurements in the high-risk areas.