Laboratory assessment of the performance and elastic behavior of asphalt mixtures containing steel slag aggregate and synthetic fibers

This study focused on the assessment of the performance of fiber-modified asphalt mixtures containing steel slag aggregates. The asphalt mixtures incorporating coarse steel slag aggregate were reinforced with three types of synthetic fibers polyvinyl alcohol, acrylic and polyester at the dosage of 0.3% by weight of the aggregates. The performance tests were resilient modulus, rutting resistance, moisture sensitivity and cracking resistance. The results showed that the resilient modulus of the reinforced mixtures was slightly lower than the reference mixtures at all frequencies. Additionally, the rut depth of the reinforced mixtures was lower than the reference mixtures due to the densification. Otherwise, the reinforced asphalt mixtures showed better resistance to rutting than the control mixtures after excluding the deformation caused by the densification. The indirect tensile strength and tensile strength ratio of the reinforced asphalt mixtures were higher than the mixture containing steel slag aggregate. The cracking resistance of the reinforced mixture was the best in comparison with the other mixtures at the applied load at the high frequencies. While the reinforced asphalt mixtures showed the worst resistance to cracking at the applied load with low frequency of 2.5 Hz.