Application of Statistical Methods in Evaluating Asphalt Mixture Homogeneity

Homogeneity is one of the most important factors affecting the performance-related properties of asphalt mixtures. Pavement condition surveys have shown various patterns of distress due to segregation and other types of non-uniformity. Using digital image processing, a statistical method was developed to evaluate asphalt mixture homogeneity quantitatively. Aggregate particle distribution in asphalt mixtures was described and analyzed by aggregate particle frequency statistic and distance statistic. The index of homogeneity was presented through aggregate particle distribution. The relevance of homogeneity to some mixture performance properties was also investigated. Results show that asphalt mixture homogeneity can be assessed quantitatively by the values of aggregate particle frequency statistic and distance statistic. Moreover, homogeneity dominates variations in mixture performance properties.