Rheological Properties and Microstructural Analysis of Asphalt Binder Doped with Anti-Stripping Agent after Aging

In order to comprehensively explore the long-term durability of asphalt mixed with an anti-stripping agent, laboratory tests were carried out on base asphalt, SBS modified asphalt and base asphalt mixed with an anti-stripping agent after long-term aging. The rheological properties, chemical composition and microscopic morphology of the three asphalts before and after aging were compared and analyzed from macroscopic and microscopic angles. The results show that the modulus of asphalt is more affected by temperature than aging, and the anti-aging ability of the asphalt with the anti-stripping agent is better than that of base asphalt and slightly worse than that of SBS modified asphalt. The change in the absorption peak intensity before and after the aging of asphalt with the anti-stripping agent is the same as those of the base asphalt and SBS modified asphalt at 2920 cm−1 and 2850 cm−1, while the opposite pattern is observed in other four places. The honeycomb structures of the base asphalt and SBS modified asphalt became longer and the number of peaks increased slightly after aging. However, the asphalt surface with the anti-stripping agent had no obvious honeycomb structures before aging, and there were obvious honeycomb structures after aging, the number of which was between those of the base asphalt and SBS modified asphalt after aging; moreover, the lengths of honeycomb structures were still significantly smaller than those of the base asphalt after aging. This study investigated the performance changes of the anti-stripping-agent asphalt before and after long-term aging at multiple scales and compared the asphalt mixed with the anti-stripping agent with base asphalt and SBS modified asphalt to fully evaluate its long-term durability.