Application of density gradient column to flexible pavement materials: Aggregate characteristics and asphalt absorption

Accurate measurements of aggregate volumetric properties are essential to a satisfactory mix design and successful production of pavement. Moreover, determination of aggregate asphalt absorption is required to correctly estimate air voids and optimal binder content. The objective of this research was to apply the density gradient column technique to flexible pavement materials and to investigate aggregate volumetric properties, asphalt absorption and their possible correlation. Results indicated that the density gradient column can accurately measure piece-by-piece volumetric properties and asphalt absorption, and revealed a very good correlation between asphalt absorption and aggregate void volume (as reflected by the aggregate bulk density).