Comparative Evaluation of WMA Additives Effects on Conventional and Polymer Modified Asphalt Pavements

Abstract

This study is mainly focused on the evaluation of the effect of Warm Mix Asphalt (WMA) additives on the performance grade of straight and polymer modified asphalt binder and the performance of asphalt mixtures. In order to analyze these effects, the Performance Grade (PG) of asphalt binder and the degree of compaction of WMA mixtures with various additives were examined initially. Moreover, the degree of compaction was evaluated in field test sections. Lastly, the effect on WMA performance were evaluated using wheel tracking test and indirect tensile (IDT) strength test for the rutting resistance, moisture susceptibility and crack resistance, respectively. Based on the laboratory and field test results, it can be concluded that WMA additives can affect the PG grades of conventional but not for polymer modified asphalt binder while viscosity related to mixing and compaction results in conversely. From the field test, the rutting and crack resistances of WMA pavements are higher than HMA pavements in most cases.