Search

Nano-CaCO3 and styrene-butadiene-styrene block copolymer （SBS） were used as additives to prepare nano-CaCO3/SBS composite modified asphalt. The optimum amount of admixture was determined by testing basic physical properties, the performance and micro morphology of asphalt were investigated by rheological property and segregation test, fluorescence microscope observation and thermogravimetric analysis. The results showed that the best proportion of the two admixtures was 5% （mass fraction, the same below） of nano-CaCO3 and 4% of SBS. After adding SBS into nano-CaCO3 modified asphalt, the viscosity of the composite modified asphalt increased at different temperatures, high temperature rutting resistance and low-temperature performance was significantly improved, and storage stability was good. Nano-CaCO3 molecule, SBS molecule and matrix asphalt molecule had good compatibility, and the thermal stability of asphalt was enhanced because of the composite modification.