Cold-mixed epoxy asphalt binder (CEA) has attracted increasingly attention as a superior steel bridge pavement material for its convenient construction and low energy consumption. In this paper, the compatibility of CEA was improved with the addition of epoxidized soybean oil (ESO) and evaluated by fluorescence microscope (FM), dynamic thermomechanical analysis (DMA) and mechanical properties. The compatibility mechanism was studied by Fourier transform infrared spectrum (FTIR) and molecular dynamics simulation (MD). The result showed that the addition of ESO made asphalt particles disperse smaller and increased elongation at break of the CEA to 108.1%. In addition, it reduced the number of Tg of the CEA to one. These mechanism may be as a result of: (1) the reaction between ESO and benzene ring in asphalt, narrowing the polarity difference between asphalt and epoxy resin, (2) the decrease of the cohesion energy densities and solubility parameters of epoxy resin and asphalt, (3) the larger interaction energy of the whole system due to ESO. Key words: Cold-mixed epoxy asphalt; Compatibility; Epoxidized soybean oil; Mechanism; Molecular dynamics simulation

CICTP