Characterization of asphalt mastics reinforced with basalt fibers

This paper examined the effect of basalt fibers of varied lengths (6 mm, 9 mm and 15 mm) and contents (3-10%) on the properties of asphalt mastics. For comparison, three asphalt mastics reinforced with basalt fiber, lignin fiber or polyester fiber were investigated. The asphalt adsorptivity, shear behavior, crack resistance and high-temperature rheological property were evaluated by leakage test, cone penetration test, strip-tensile test and dynamic shear rheometer test, respectively. In order to understand the reinforcement mechanism, the microstructure and morphology of basalt fiber-asphalt mastics were studied through using scanning electron microscopy (SEM). It was shown that the addition of basalt fibers generally improved the properties of asphalt mastics especially the crack resistance. The asphalt adsorption and strength behavior of asphalt mastic with 6 mm basalt fiber excelled that with 9 mm or 15 mm due to its largest contact area with asphalt mastic. The crack resistance and high-temperature rheological property of asphalt mastics were influenced by the adsorption and content of fibers. The asphalt mastic with basalt fiber showed the best comprehensive performance among all types of fiber-reinforced asphalt mastics. Basalt fibers could form a stable three-dimensional network in the asphalt mastic, which was able to disperse the stress and suppress the development of cracks of asphalt mastic effectively.