Designing skid resistance testing programs using videotaped road inventory data

Abstract

It is generally accepted that road skid resistance should be carefully monitored. However, system-wide testing programs are generally expensive in terms of both manpower and equipment costs. Programs that test only road sections where the road surface is either inadequate or of marginal quality would be more economical than one in which all roads are tested, particularly where a significant proportion of the road surfaces in the system are clearly adequate. This paper examines the potential for using videotaped road inventory data to identify road sections that are either slippery or of marginal quality in terms of skid resistance. It reports on research conducted which examined the ability of individuals to identify inadequate road sections and discriminate these road sections from those with good surfaces by using VHS and super-VHS road inventory videotaped images. Videotaped records of road sections were evaluated by a panel. Their responses were then compared with skid resistance test data. A statistical analysis showed no satisfactory level of agreement between measured data and video evaluations for the VHS records. A second series of tests was conducted using super-VHS technology. The results of the second series of tests showed much better agreement. The research provided promising results and it would appear that videotaped road inventory data could be used as part of a protocol that could be developed to identify the sections that should be field tested as part of a system-wide skid resistance monitoring program.Key words: highway safety, skid resistance, program design, pavement characteristics, video evaluation.