It is well known that a newly placed surfacing aggregate polishes down to an approximately 'equilibrium skid resistance level'. This equilibrium level has been thought to be based upon the aggregates resistance to polishing and the traffic loads placed upon it. This paper examines the variation of skid resistance after equilibrium level has been reached which is commonly known as seasonal variations. Changes in measured skid resistance following the simulated effects of rainfall and contaminants have been determined. The laboratory results show significant variations do occur in the measured skid resistance. These variations have been shown to be related to the particle size and the hardness of the contaminants as well as the aggregate type. (a) For the covering entry of this conference, please see ITRD abstract no. 0612AR242E.
Samenvatting