Self-healing properties of ferrite-filled open-graded friction course (OGFC) asphalt mixture after moisture damage

Porous asphalt pavements have been widely used because of their advantages of drainage and noise reduction. However, these pavements are susceptible to moisture damage due to the characteristically large portion of air voids. Therefore, the maintenance of porous asphalt pavement has become one of the research hotspots. Microwave technology is generally used as a kind of high-efficiency maintenance method, but now it is also recommended as the technology to heal the micro-cracks in the pavement. However, there is little research conducted on its healing efficiency of asphalt mixture suffered from moisture damage. In this paper, the influence of ferrite content on the pavement performance, mechanical properties and heating effect was studied. Through the indirect tensile fatigue test, the effects of microwave heating time, healing time and damage degree on the self-healing efficiency of moisture damaged asphalt mixture before and after microwave heating were studied based on the evaluation indexes of the fatigue life extension ratio and fatigue life recovery ratio. It is found that the optimal microwave heating time and optimal healing opportunity of OGFC-13 asphalt mixture with 5% ferrite are 120 s and 50% damage degree respectively. In addition, the longer the healing time, the better the healing effect, but the influence of the healing time is smaller compared with the heating time. (C) 2019 Elsevier Ltd. All rights reserved.