Preparation and multi-evaluation of durability for superhydrophobic anti-icing coating on asphalt pavement

In response to the demand for passive de-icing technology on asphalt pavements, this study commenced with the superhydrophobicity principle and developed a superhydrophobic anti-icing coating for asphalt surfaces. Considering the unique characteristics of pavement engineering, we conducted a systematic investigation and evaluation regarding the compatibility between the coating and asphalt surface, extreme environmental tolerance, and durability performance of the coating. Firstly, nano SiO₂-coated carbon nanotubes (CNTs) were synthesized using sol-gel technology, followed by surface modification through dodecyltrimethoxysilane to obtain superhydrophobic nano fillers. By optimizing the spraying process, a uniform and smooth structure for the superhydrophobic coating was achieved. Finally, comprehensive microstructure analysis of the coating was conducted alongside its implementation on asphalt surfaces. The results demonstrated that the coating exhibited superhydrophobic properties (CA = 154.7°) due to the micro-nano secondary structure and the presence of hydrophobic groups. The adhesion between the coating and pavement was robust. Moreover, at low temperature condition (-20 ℃), the bonding strength between the coated pavement and ice was 0.723 times that of direct ice-pavement bonding strength, indicating an excellent anti-icing effect. The skid resistance performance of asphalt concrete surfaces coated with the superhydrophobic coating met the specification requirements. In the long term, this superhydrophobic pavement material offers significant economic benefits owing to its exceptional and comprehensive road performance.