Skid resistance characteristics of asphalt pavements in hot climates

This research assesses the influence of temperature variation on GripTester (Findlay Irvine, Penicuik, Scotland) skid resistance measurements of asphalt pavements in Qatar. It evaluated a test road with six different sections and four major highways during winter and summer seasons with ambient temperature ranging from 18 to 44°C. Close-range photogrammetry (CRP) was employed for surface texture analysis using multiple pavement surface images and proprietary software. Differences in binder type and mixture design of the test road sections did not cause significant differences in skid resistance. The south-north (SN) direction of the test road had lower friction values during summer than winter. The opposite was the case for the north-south (NS) direction. The average friction and corresponding texture parameters in the NS direction were respectively 1.4 and 1.2 times higher than in the SN direction. The major highways generally had lower friction in summer than the following winter despite traffic polishing over time. The results suggest that the effect of temperature on skid resistance becomes pronounced when the grip number drops below 0.30 and surface texture decreases.