Investigation of the Wet and Thermal Conditions Effect on the Micro-Scale Characteristics of Interfacial Transition Zone of Porous Asphalt Mixture

Complex environmental factors can significantly influence the micro-properties of porous asphalt (PA) mixture. Therefore, effects short-term and long-term thermal aging moisture immersion on micromechanics properties, micro-morphology, chemical element distributions interfacial transition zone (ITZ) PA mixture were studied to reveal mechanisms by which degradation impact performance means nanoindentation (NI), backscattering scanning electron microscope (BSEM), energy-dispersive X-ray spectroscopy (EDS) analysis techniques. The results show that ITZ is not softest part mixture, order modulus aggregate > mastic. thickness about 10–20 μm. Thermal has negligible effect width ITZ. With increasing degree, mastic increase, while water damage reduces slightly increases little morphology ITZ, will lead microcracks micropores in Compared with aging, a greater leads softening phase. obtained EDS line basically consistent nanoindentation. Overall, external have more significant mechanical properties than micro-morphology outcomes this research provide better understanding service environment microscopic characteristics