Volume 35, Issue 6 (November 2007)
Relationship of Aggregate Microtexture to Asphalt Pavement Skid Resistance
Aggregate properties are one of the important factors that influence the asphalt pavement skid resistance. This paper presents a detailed analysis of aggregate texture and its relationship to pavement skid resistance. A new method is developed for the evaluation of aggregate resistance to polishing. This method relies on the Micro-Deval test as the mechanism for polishing aggregates and the Aggregate Imaging System (AIMS) for quantifying the change in texture due to polishing. The results show that the Micro-Deval test is an effective method for polishing aggregates within a short time. Also, the AIMS texture analysis is able to rapidly and accurately quantify the influence of polishing on texture. The verification of the new method was achieved through measuring the skid resistance of pavements constructed using three different aggregate sources and three different aggregate gradations. The skid resistance was found to be related not only to average aggregate texture, but also to the texture distribution within an aggregate sample. The developed method can be used in models for predicting the change in asphalt pavement skid resistance as a function of aggregate texture, mixture properties, and environmental conditions.