Using recycled taconite as alternative aggregate in asphalt pavements

Current demand from transportation agencies for construction and maintenance of their pavement network requires the use of large amounts of aggregate. Diminishing reserves of aggregate and environmental regulations for new aggregate extraction sites restricts the use of standard aggregates and encourages the use of recycled materials. This paper investigates the suitability of using taconite aggregates, a byproduct of taconite mining industries, for construction of asphalt pavements by evaluating the mechanical performance of asphalt mixtures prepared with taconite aggregates. The experimental work is performed by means of the semi-circular bending test (SCB), the indirect tensile test (IDT), dynamic modulus (E∗) test, and the thermal stress restrained specimen test (TSRST) with acoustic emission monitoring. The results indicate that, in general, the mixtures prepared with taconite aggregates perform slightly better than the mixtures prepared with standard aggregates.