Project Details

Warm Mix Asphalt (WMA) and Recycled Asphalt Pavement (RAP) are two popularly used sustainable technologies in the pavement industry. The use of some WMA technologies may increase the moisture susceptibility of the mixtures, and the use of RAP material can affect long term durability and workability. The combination of WMA and RAP technologies together can address the problems that could arise if these technologies are used individually. Two WMA technologies – Evotherm and Foamer, and three RAP contents – 0%, 20% and 40% were used in this study to produce mixtures. Workability and moisture susceptibility of these mixtures were compared to that of a virgin HMA mixture using compaction data and Tensile Strength Ratio (TSR) respectively. The effectiveness of Evotherm as an anti-strip additive in addition to being a WMA additive was also evaluated using TSR test. Workability and TSR ratio was observed to decrease with increase in RAP content for similar mixtures while the (ITS) Indirect Tensile Strength values increased.  With high RAP content, WMA mixtures with standard binder grade performed better than corresponding HMA-RAP mixtures with softer binder.