Healing Performance of Granite and Steel Slag Asphalt Mixtures Modified with Steel Wool Fibers

摘要

This paper evaluates the induction healing performance of granite and steel slag asphalt mixtures modified with Steel Wool Fibers (SWF). A computerized tomography scan (CT-scan) was conducted to analyze microstructure and distribution of steel wool fibers in the mixture. Thermal conductivity was examined and heating rate was investigated with induction heating system. The healing performance was investigated by crack-heal cycles with three-point bending test. Dynamic modulus and repeated indirect tensile test were carried out to characterize the mechanical properties of asphalt mixtures modified with SWF. The results showed that the conductive properties and induction heating rate of asphalt mixture was enhanced by adding steel wool fibers and steel slag. The microanalysis results showed the agglomeration and uneven distribution of fibers in the mixtures when the mixed conductive additives exceed a certain dosage. It was found that heating rate of steel slag mixture was higher than that of granite mixture; however, its healing performance was slightly lower because of the cracking of weak steel slag. Finally, the mechanical test results demonstrated that the rutting resistance of asphalt mixtures was enhanced by adding steel wool fibers.