Effects of waterborne epoxy resin on the fatigue performance of bitumen emulsion

Bitumen emulsion faces the major concern of low mechanical strength, especially at high service temperatures. To improve the mechanical performance of bitumen emulsion, waterborne epoxy resin was used as a modifier in this study. The effects of waterborne epoxy resin on the fatigue performance of bitumen emulsion were evaluated in this study using both the stress-controlled time sweep test and linear amplitude (LAS) test. The dissipated energy concept and viscoelastic continuum damage (VECD) theory were adopted to analyze the fatigue testing data obtained from the time sweep test and LAS test, respectively. It is found that the fatigue life of the emulsion residues increased with the incorporation of waterborne epoxy resin from the time sweep test conducted at the stress levels from 300 kPa to 500 kPa. On the other hand, the LAS test indicated that the trend of the predicted fatigue life of the emulsion residues was strain dependent.