Effect of dumped iron ore tailing waste as fine aggregate with steel and basalt fibre in improving the performance of concrete

Abstract The present study investigates the effects of utilizing dumped waste as a practical resource for making concrete. In this regard, waste marble powder used a filler material replacing a smaller constant portion of cement, dumped iron ore tailings (IOT) were used as a partial replacement for fine aggregate in different proportions. Since waste materials are added in both cementitious and fine aggregate content, to improve the strength and to make the concrete denser and less porous ground granulated blast furnace slag (GGBS) and nano-silica (nS) were used as supplementary cementitious materials for cement. They were added in a constant replacement level of 7.5% and 0.5% respectively, with a constant replacement level of 7% of marble powder, making a 15% replacement of the cementitious materials by cement weight. The replacement percentages adopted for IOT were 0%, 20%, 30% and 40% by fine aggregate weight. 0.5% Steel fibres and a hybrid combination incorporating 0.25% steel fibre and 0.25% basalt fibres were also used to improve the concrete's tensile and flexural properties. The Specimens were subjected to various tests related to strength such as compression, flexure and few durability tests such as deterioration, sorptivity and porosity. The results were compared with traditional concrete. The optimum mix was identified as the one with 30% IOT and hybrid fibre combination.