Study on the de-icing performance of micro-surfacing mixtures using different lithological aggregates

Snow accumulation and ice formation on roads in winter not only endangers traffic safety and traffic efficiency, but also directly damages the pavement structure. To explore how aggregates of different lithologies affect pavement anti-icing performance, this study modified emulsified asphalt with SBR (Styrene-Butadiene Rubber) and WER (Waterborne Epoxy Resin), used diabase, granite and limestone aggregates, replaced part of mineral powder with anti-icing filler, and prepared anti-icing micro-surfacing of different lithologies. SEM observed aggregate morphology; XRD and XRF analyzed their chemical composition and content. Meanwhile, icing, weight impact, ice adhesion, and freeze-thaw cycle-abrasion tests studied de-icing performance. Results show: surface grooves and pores of aggregates cause anti-icing filler agglomeration and uneven distribution, impairing its effect. Diabase has strong adhesion to asphalt mortar, preventing moisture penetration. A large area of diabase-based specimens remains unfrozen at −22℃, with ice layers easy to spall, showing the best anti-icing performance. After 3 freeze-thaw cycles, its abrasion value is 663.8 g/m 2 , the lowest of the three. Limestone, with high porosity, strong water absorption and rough surface, is more prone to icing and has strong ice adhesion. Granite has intermediate icing time and ice adhesion: without anti-icing filler, its post-freeze-thaw abrasion value increase rate is the highest; with 50 % filler added, the increase rate drops by 10.4 %age points, making it most sensitive to the additive. This study is the first to systematically reveal the influence mechanism of aggregate lithology on deicing performance by regulating the distribution of anti-icing fillers and interfacial effects. It clarifies that lithological characteristics are a key design parameter affecting the performance of anti-icing micro-surfacing, providing a reference for the precise material selection of anti-icing pavements based on regional aggregate resources. In summary, diabase has the best anti-icing capability, limestone the worst, and granite the most sensitive to anti-icing filler.