Using Iron Ore Tailings from Tailing Dams as Road Material

The present work aims to evaluate the feasibility of iron ore tailings from tailing dams as an alternative material for road infrastructure. The iron ore tailings were characterized according to their chemical, mineralogical, environmental, and physical properties. Subsequently, the tailings were chemically stabilized using cement, lime, or steelmaking slag as binder. The tailing-cement, tailing-lime, and tailing-slag mixtures studied consisted of 1, 2, 5, and 10% binder content, each. The characterization methodology included chemical and mineralogical analysis through X-ray fluorescence and diffraction; environmental analysis with leaching and dissolution tests; evaluation of compaction curves; California bearing ratio (CBR) tests and expansion assessment; compressive strength, with curing in moisture chamber or at open air; water absorption; and evaluation of durability of the mixtures. Overall, the results indicate that the iron ore tailings are a feasible solution for use as layers for road paving, once chemically stabilized. The cement is the most efficient stabilizer among the studied binders. The slag-tailing sample did not endure the durability cycles; thus, further research is required to ensure its technical feasibility. (C) 2016 American Society of Civil Engineers.