Investigation of anti-aging performance in nano-sol modified high-SBS content emulsified asphalt and its micro-surfacing mixtures

High-SBS content modified emulsified asphalt is susceptible to thermal and UV aging, which limits its use in micro-surfacing applications. This study investigates the use of three nano-sol materials (nano SiO₂, nano ZnO, nano TiO₂) as anti-aging agents to enhance the performance of high-SBS emulsified asphalt. Unlike traditional solid nanoparticles, nano-sol materials offer superior dispersion, stability, and reduced aggregation, effectively improving the aging resistance of emulsified asphalt. Accelerated aging tests using xenon lamps simulated natural aging processes, and changes in bonding performance and 3D surface morphology were evaluated through abrasion tests and scanning. Physical properties, rheological performance, and chemical and microstructural changes were analyzed using FTIR and FM techniques. The results show that nano-sol modified asphalt mixtures exhibit improved wear resistance, reduced crack formation, and less aggregate loss during aging. Among the nano-sol materials tested, ZnO nano-sol demonstrated the most significant anti-aging performance due to its excellent UV absorption, scattering capabilities, and thermal stability, effectively slowing SBS degradation and preventing further asphalt hardening. Despite reductions in physical and rheological properties due to aging, all three nano-sol anti-aging agents successfully delayed the deterioration of SBS emulsified asphalt, validating the effectiveness of nano-sol materials in enhancing aging resistance. •Nano-sol materials are proposed as anti-aging agents for emulsified asphalt.•Accelerated aging with xenon lamps simulates natural aging conditions.•3D digital reconstruction analyzes the surface morphology of asphalt mixtures.•Nano-sol micro-surfacing mixtures show lower wear loss and fewer cracks.•Nano-sol effectively prevent performance deterioration and SBS degradation after aging.