Effect of short-term and long-term weather on pavement surface friction

Pavement surface friction plays an important role on highway safety, specially during the wet weather. The available surface friction may vary significantly due to weather related changes in pavement surface condition. Several past studies have examined the short-term or seasonal skid resistance variation but mostly ended with unreasonable results. The effect of long-term weather on skid resistance variation is not yet studied well. The surface friction, in terms of British Pendulum Number (BPN), of both Portland cement concrete (PCC) and asphalt concrete (AC) pavements were measured bi-weekly or monthly from February to October to determine the effect of short-term weather changes on skid resistance variation. Long Term Pavement Performance (LTPP) program data for both PCC and AC pavements were used to determine the effect of long-term weather on surface friction variation. Analysis has shown that available friction fluctuates at 0.35BPN per 1°C change in prevailing ambient or pavement surface temperature with an overall eight BPN seasonal fluctuation. Prior short-term rainfall, dry-spell, and temperature were shown to be insignificant for changes in skid resistance. Similarly, prior long-term weather was shown to be insignificant for changes in skid resistance of both AC and PCC pavements.© @ Chinese Society of Pavement Engineering.