Effect of Aggregate and Asphalt on Pavement Skid Resistance Evolution

When designing pavement, engineers must optimize some requirements such as user safety (skid resistance), environmental impact (noise, rolling resistance...)... However, this skid resistance evolves during the entire pavement life. So it is a common practice to perform laboratory tests to forecast the evolution of skid resistance. Previous works done in the French Laboratory of Bridges and Roads (Laboratoire Central des Ponts et Chaussées, LCPC) have identified phenomena such as binder removal, aggregate polishing and seasonnal variations to be responsible of these variations. This paper focuses on the polished stone values of aggregates and the aging of asphalt on the evolution of pavement skid resistance. Skid resistance of different specimens of nude aggregates and asphalt mixes that are submitted to polishing and aging was studied. On skid resistance point of view, aging of aggregates can be neglected in comparison to those of asphalt. Rocks with high polishing resistance offer less variation of skid resistance. Aging of asphalt tends to increase skid resistance until 12 month and remains this latter constant after.