Utilizing Photodetection Technique to Assess Moisture Damage of Asphalt Mixtures

Abstract

In this study, asphalt mixtures were subjected to the boiling water test, and the stripping potential was quantified in terms of loss index using the photodetection technique. Initially, the change in loss index due to variability in testing protocols like boiling time, drying time, and drying method was evaluated. Subsequently, loss index (LI), and tensile strength ratio (TSR) were determined for three different aggregate types, five liquid anti-stripping additive contents, and four dosages of hydrated lime. Results indicated that LI increased with the increase in boiling time, whereas LI decreased due to moisture. In terms of the drying method, the recommended hot-air-gun drying method was suitable for quantifying stripping. Furthermore, the results of both LI and TSR had a good correlation. The threshold limits for LI with respect to specified TSR requirement was evaluated and was found to be sensitive to variation in aggregate type and additive content. Therefore, LI values estimated using a quick tool could facilitate quality control during the asphalt mixture’s production stage.