Asphalt pavement coated by hot-pressed hydrated lime

Hot-pressed hydrated lime (HL) on the surface of asphalt pavements forms a type of light-coloured cool pavement, which is called hot-pressed HL pavement. In this cool pavement, unmodified HL at the millimetre particle size is commonly used. This study used HL with three particle sizes (1200, 600, and 200 mesh), modified by graft polymerisation and emulsion polymerisation. The cooling effect and laboratory performances (skid resistance, abrasion resistance, anti-glare performance, and erosion resistance) were evaluated. The effects of particle size and surface modification were evaluated, and the cost of this cool pavement type was analysed. Hot-pressed HL reduced the surface temperature of asphalt pavement by about 10 degrees C. The decreased particle size of HL improved both the cooling effect and the erosion resistance. HL modification slightly decreased the cooling effect, but significantly enhanced abrasion resistance, anti-glare performance, and erosion resistance. A particle size of 1200 mesh, spreading dosage of 100 g/m(2), and graft polymerisation modification are recommended for HL. Noteworthy, the cooling effect of hot-pressed HL pavements is slightly weaker than that of traditional heat-reflective coating pavements; however, the cost of the former material is only about 0.01 times of the latter.

Automated summary

The study found that using different particle sizes and modifications of hot-pressed hydrated lime (HL) can improve the cooling effect and performance of asphalt pavements, with a particle size of 1200 mesh, spreading dosage of 100 g/m(2), and graft polymerisation modification being the optimal choices for HL. The cooling effect of hot-pressed HL pavement is slightly weaker than traditional heat-reflective coating pavements, but the cost of the former is only about 0.01 times of the latter.