Project Details

In this study, an attempt was made to determine the effect of prolonged heating on the bond strength between aggregate and asphalt that contained anti-strip additives (LOF 6500 and Morelife 2200). On account of the substantial decrease of anti-strip additive contents for both asphalt binders and mixes when subjected to prolonged heating, whether the loss of additive content due to storage and transport at elevated temperatures affects mix performance in terms of moisture sensitivity or not, was evaluated in this study. A series of tests, namely Tensile Strength Ratio Test (TSR), Contact Angle test, Pneumatic Adhesion test and Atomic Force Microscopy (AFM) test were performed, and the results obtained from each of these tests were compared to come to a reliable conclusion regarding effectiveness of the various tests for assessing the effect of prolonged heating on the adhesive bond strength. Results obtained from the Tensile Strength Ratio test clearly show that as the prolonged heating duration increased the TSR values failed the limiting value of 85% as followed by NCDOT specification in as little as six hours and continued to further decrease with heating duration. ​