Anti-icing properties of superhydrophobic coatings with hierarchical structure surfaces on asphalt pavement

The formation of ice on pavement in winter has a negative impact on road traffic safety. This study improves the anti-icing property of pavements by preparing a superhydrophobic coating for asphalt pavements to ensure traffic safety. Here, a superhydrophobic coating with a hierarchical structure (SCH) was prepared using a resin, nano-silica powder, and other materials. The maximum contact angle was 160.5°. Through scanning electron microscope, confocal 3D microscope, and contact angle tests, it was observed that the SCH has the most complex surface texture (Ra=16.69 μm, Rz=65.02 μm) and significant hydrophobic performance (contact angle=160.5°) than the superhydrophobic coating with a single-level structure surface (SCM, SCN). Based on the ice-road shear adhesion theoretical results and ice-road shear test results, it can be concluded that, at a temperature of −10 °C, SCH with a hierarchical surface structure has stronger anti-icing property than SCM and SCN. Pavement friction tests reveal that SCH has a minimal impact on the friction coefficient (μ=0.643), still meeting the requirements for anti-skid property. Furthermore, accelerated wear tests indicate that SCH maintains sufficient wear resistance on the pavement. After accelerated wear tests, compared with SCM and SCN, it still has the best anti-icing property. SCH exhibits significant hydrophobic, anti-icing, anti-skid, and anti-wear properties, providing reference for the development and implementation of novel anti-icing technologies for pavement. •The contact angle of SCH is 160.5°.•The superhydrophobic coating reduce the ice-road shear adhesion by 83.8%.•Hierarchical structure surfaces exhibit more significant anti-icing properties.•SCH exhibits good skid resistance and durability.