Moisture Damage of Asphalt Mixes Modified with SEAM Pellets

In China, the use of Sulfur Extended Asphalt Modifier (SEAM) has been recently introduced to the pavement community. This asphalt modifier does not only conserve energy, reduce asphalt content by 16%–40%, but also has good performance in terms of high strength and good rutting resistance. Preliminary experience with asphalt mixtures containing SEAM showed vulnerability to moisture damage. To improve upon resistance to moisture damage, large number of experiments was conducted, such as retained Marshall Stability, Freeze-thaw, and split test on four different types of aggregate, and five different types of anti-stripping agents. The influences of gradation, air void and asphalt content on reducing moisture damage due to the inclusion of SEAM were also analyzed. The improvement to different aggregate caused by different anti-stripping agent differs significantly. Using coarser gradation yielded higher resistance to moisture damage of mixtures containing SEAM.