Improving the field compaction of asphalt pavements using X-ray CT and imaging techniques

This paper reports on the findings from a study that focused on evaluating the influence of different compaction patterns on asphalt pavement uniformity in terms of air void distribution. A number of projects with different asphalt mixture types were compacted, and cores were extracted at different locations from these projects. The X-ray Computed Tomography system was used to capture the air void distributions in these cores. The images were used to develop maps of air void distributions across the pavement surface and depth that were useful to study the uniformity of air void distributions. The analysis results have revealed that the uniformity is highly related to the sequence of using different compaction equipment. More importantly, the efficiency of compaction at a point is a function of the location of this point with respect to the roller compactor width. The results could be used to develop the compaction patterns in order to construct pavements with uniform air void distribution.