Assessment of mechanical and micro structural analysis of iron ore tailings and red mud sustainable bricks using multiple linear regression

Abstract The synergistic utilization of mining and industrial wastes in the construction industry represents a major step forward in the environmental and sustainable constructions. This research has presented an exploration of the feasibility of combined use of iron ore tailings (IOT) and red mud (RM) in sustainable brick manufacture. The IOT and RM have been blended with ground granulated blast furnace slag (GGBS) and lime solution for the production of bricks without high-temperature kiln-firing. Eight different combinations of (IOT + GGBS) and (RM + GGBS) with varying ratios of the principal components have been used in the sustainable bricks. Multiple regression analysis has been employed to estimate the strength of a different compositions of bricks. The bricks with 70% RM and 30% GGBS have attained the highest strength of 9.68 MPa and the bricks with 70% IOT and 30% GGBS attained the highest strength of 6.25 MPa among various combinations. The water absorption results of 18.7% and 19.02% have fulfilled the IS standards too. The research has revealed that the bonding between bricks and mortar has been influenced by the Si-Al matrix at low calcium content. Additionally, the formation of the delicate Ca-Al-Si phase capable of permeating the brick, has contributed to the constructive brick structure. The study also reinforced the view that the combined use of mining and industrial waste in production of environmentally friendly bricks is viable.