Performance enhancement of engineered cementitious composite through tailoring recycled iron sand

Abstract

Engineered cementitious composite (ECC) possesses predominant tensile properties while a relatively low modulus of elasticity (MOE) due to the low sand-to-binder ratio and fine quartz sand (QS, QS-ECC). Further, the excessive consumption of QS in concrete industry has imposed a serious challenge to natural resource preservation. Iron sand (IS), a by-product of the iron industry with high particle modulus, could be a potential alternative in developing ECC (IS-ECC). This research focused on recycling IS as fine aggregate to develop a sustainable ECC with high mechanical performance, especially high MOE. The influences of water-to-binder ratio, sand-to-binder ratio, and IS particle size were systematically investigated. The results indicated that all the IS-ECC demonstrated robust tensile performance with the tensile strength and strain capacity over 5 MPa and 5%, respectively. Compared with the QS-ECC, a comparable or even superior compressive strength was achieved by all the IS-ECC. Impressively, the MOE of IS-ECC with 20–40 and 40–80 mesh of IS particles exhibited 68% and 60% higher than that of QS-ECC, respectively. SEM observations well reflected the macroscopic tensile performances. The cost and environmental effect analysis revealed the sustainability of IS-ECC. This research provides the groundwork for promoting the utilization of IS in developing high performance ECC material.