Properties and microstructure of IOTs Concrete

Abstract

ABSTRACT Successful utilization of waste materials such as agro, urban and industrial waste in concrete depends on its use being economically competitive with the alternate natural material. In this study, Iron ore tailings (IOTs), an industrial waste product, generated during the production of iron ore, is used in its natural state as fine aggregate to partially replace sand, for the production of normal strength concrete. The use of this waste material brings about conservation of declining natural resources, the utilization of valuable land for more profitable use and economic advantage in comparison to the conventional material. The physical properties of the Iron ore tailings were determined and compared with that of natural sand. Fresh and hardened properties of concrete were evaluated. Field emission scanning electron microscopy (FESEM) images of fine aggregate materials and the hardened concrete produced, were also studied. The microstructure of IOTs concrete samples shows a tighter interface between the cement gel and the aggregate when compared with those of the control concrete sample having no IOTs. The outcomes of mechanical properties tests and the microstructure analysis reveals that the IOTs was able to improve the strength and denseness of concrete. Based on findings from this research, it can be concluded that IOTs can be used to partially replace sand as fine aggregate in concrete, in order to improve the mechanical properties and the pore structure of the concrete.