Study of Curing Reaction Mechanism and Construction Control Performance of Epoxy Asphalt

Scanning electron microscopy and fluorescence microscopy were applied to observe the micromorphology of new epoxy asphalt N-EA with a view to analyze the curing reaction and transition mechanism between thermoplasticity and thermoset of N-EA. Through this method, the construction control performance of N-EA epoxy asphalt was investigated under the best mixed resin dosage condition, such as mixing holding temperature, construction control time, strength development, etc. The results showed that 37% mixed resin is the inversion amount of N-EA changed from thermoplastic to thermoset of epoxy asphalt. N-EA with 38% mixed resin will form cross-linked network structure, epoxy resin is the continuous phase, and exhibits thermosetting properties. N-EA with 50% mixed resin has formed a well-distributed and dense three-dimensional cross-linked network structure, in which asphalt plays a good toughening role. N-EA mixture exists in wide range in construction temperature and time control. The longest reserved time of the mixture was 3h at the reserved temperature of 165-185℃. The mixture possesses high bending elasticity modulus and deformation performance and it has better combination property at 175℃. Before the mixture is fully solidified, the temperature and time of health maintenance are the key factors of its strength growth, the mixture is maintained at 40℃ for 4 days and its Marshall stability is higher than 50kN, to meet the requirements of open traffic. © 2020, Editorial Department of Journal of Building Materials. All right reserved.