Utilization of Electric Arc Furnace Slag as Coarse Aggregate in Portland Cement Concrete Pavement

Natural aggregates such as stone chips are becoming increasingly scarce in Bangladesh with urbanization. The infrastructure construction of Bangladesh highly depends on the stones imported from nearby countries. On the other hand, industrial by-product like slag, generated during steel production is a problem for direct disposal. These steel slags can be a potential alternative material in construction. Induction furnace slag and electric arc furnace (EAF) slag are available in Bangladesh. Over the past decades, the steel production of both types has increased. As both of the slags have different chemical composition, they have to be treated differently. This investigation only focuses on the performance of EAF slag when they are used as a coarse aggregate in Portland cement concrete pavement.

Stone chips were replaced 10%, 20%, 30%, 40%, 50% and 60% respectively by EAF slag. Cylindrical concrete specimens (100 mm by 200 mm) and concrete beam specimens (300 mm by 100 mm) were made. The cylindrical concrete specimens were tested at 3, 7, 14, and 28 days for compressive and tensile strength. The concrete beam specimens were tested at 14 and 28 days for flexural strength. Results show that the compressive strength of concrete increases till 20% replacement of stone chips with EAF slags and then starts to decrease. At the optimum replacement, the compressive strength is 20% higher than the control mix. Similarly, the tensile strength and flexural strength increase till 40% replacement of stone chips with EAF slags and then start to decrease. The tensile strength at optimum replacement is 50% higher and flexural strength is 100% higher than the control mix. Therefore, the use of EAF slag can contribute to the long-term development of rigid pavements in Bangladesh as well as solve the environmental crisis.