Evaluation of the performance of warm mix asphalt in Washington state

Warm mix asphalt (WMA) is a relatively new and emerging technology for the asphalt industry. It offers potential construction and environmental advantages over traditional hot mix asphalt (HMA). However, WMA must perform at least as well as HMA before it can be used extensively. This study evaluates the performance of WMA mixtures and their corresponding HMA control mixtures obtained from various field sites in the state of Washington. Four WMA technologies are examined, including Sasobit((R)) and three water-foaming technologies, Gencor((R)), Aquablack and ALmix Water Injection. Performance tests are conducted on the field cores to evaluate and compare the rutting, moisture susceptibility, fatigue and thermal resistance of WMA and HMA, respectively. Also, the extracted binders from the field cores are evaluated. In addition, the early-age field performance of WMA and HMA control pavements are compared.