The Effect of Using Commercial Red and Black Iron Oxides as a Concrete Admixtures on its Physiochemical and Mechanical Properties

Abstract

Study discuss the effect of using commercial red and black iron oxides (RIO and BIO) as a concrete admixtures in percentages do not exceeded 2.5% of each oxide from the amount of cement, this study tested the effect of every portion from each oxide at different ages on the compressive strength as well as the workability represented as a values of slump. We conclude that the optimum portion of RIO is 2.5%, but for BIO is 1%, while the proposed uses of RIO in concrete technology are retarder through slump increment reach to 50%, coloring material and mineral admixture through Compressive Strength increment (7-365 days) 5.5-12.8%. On the other hand BIO will propose as, coloring material and mineral admixture through Compressive Strength increment (7-365 days) 22.2-30.8%. SEM-images are clearly show the formation of Calcium hydroxide phase at 7-days while at 1-year the C-S-H phase is a predominate one, in both cases of RIO and BIO. XRD-pattern is supported the results outcomes through SEM-images.