Evaluation of the induction healing effect of porous asphalt concrete through four point bending fatigue test

The objective of this paper is to evaluate the induction healing effect of steel wool reinforced porous asphalt concrete. The four point bending fatigue resistance of the beams was first studied. It was found that the fatigue resistance of these steel wool reinforced beams was quite good compared with the references in the literature. Then, fatigue life extension ratio and flexural stiffness recovery of the beams were used to show their healing effect. The fatigue life extension ratio was measured after introducing induction heating and letting the fatigue damaged beams rest. It was found that induction heating increases the healing rate of the beams and that the healing is highly microstrain-dependent with higher healing rate under high microstrain level. It was also found that the optimal heating temperature is 85 °C to obtain the best healing effect. Heating too much can cause swelling in the specimens, which will decrease the total healing produced. The fatigue damaged beams obtained extra stiffness recovery when induction heating was applied to them. Finally, it was also found that fatigue life of porous asphalt concrete can be significantly extended by applying multiple induction heating. Based on these findings, it is concluded that the self healing effect of porous asphalt concrete can be increased by induction heating the material. Additionally, the durability of porous asphalt pavement will also be improved with induction healing.