Phase Behavior and Mechanical Properties of Asphalt Modified with Low Cross-linking Epoxy Resin

The matrix of asphalt modified with low cross-linking epoxy resin varies from resin phase to asphalt phase with the increasing of asphalt content. Six levels of asphalt faction specimens were used to study the phase transformation behaviors. Direct tensile tests and Dynamic Mechanical Analysis (DMA) were performed, and Scan Electron Microscopy (SEM) was applied to observe phase morphology using trichloroethylene with the etched fracture surface. The results showed that when the asphalt volume fraction was above 0.400, the phase transformation occurred and the resin matrix phase changed to asphalt matrix phase resulting in a rapid decrease of the mechanics performance, disappearing of the platform in high-temperature zones of the storage modulus and double peaks of the loss modulus. The critical range of asphalt volume fraction of phase transformation for this modified material was between 0.400 and 0.500.