Laboratory and Field Evaluation of Asphalt Concrete Mixture Workability and Compactability

Polymer-modified asphalt have been proven to improve mechanical characteristics of asphalt mixes, however there are concerns that mixes become drier and more difficult to compact. This study aims to develop compaction indices using routine laboratory compaction procedure to evaluate the workability and compactability of hot and warm mixes prior to laydown. Workability is reflected in the ease of blending while compactability is reflected in the mixes' stability and resistance to densification. To quantify thresholds for the indices, laboratory and accelerated field testing were implemented. The workability index was tentatively found to be a minimum of 4.5 while the compactability indices were tentatively found to be a maximum of 0.5 and a minimum of 20. The compactability indices were capable of predicting mix resistance to permanent deformation.