Effects of phase-inversion waterborne epoxy resin on properties of cold patch waterborne epoxy emulsified asphalt

In order to evaluate effects of waterborne epoxy resin prepared by the phase-inversion method (phase-inversion waterborne epoxy resin) on properties of waterborne epoxy emulsified asphalt for cold patch engineering of asphalt pavement, a series of methods for evaluating properties of emulsified asphalt and casting resin were used. Results show that, with an increase in waterborne epoxy resin content, penetration, ductility, surface curing time of waterborne epoxy emulsified asphalt decrease and its adhesion degree, shear strength and bond strength increase. Moreover, its penetration, ductility and adhesion degree remain unchanged when the content of waterborne epoxy resin exceeds 20%, and its shear strength and bond strength increase most remarkably when the content of waterborne epoxy resin increases from 10% to 20%. The test results are explained by the surface fluorescent micromorphology of cured waterborne epoxy emulsified asphalt that, with the increase in waterborne epoxy resin content, epoxy resin particles firstly appear as segregated spots, and then change from spotted status to clustered status, and the epoxy resin phase gradually becomes a continuous phase. In conclusion, phase-inversion waterborne epoxy resin has effects on properties of the cold patch waterborne epoxy emulsified asphalt, and recommended content of waterborne epoxy resin is 20%.