Comparative analysis of quaternary blended self-compacting concrete (QBSCC) mixes incorporating induction furnace slag (IFS) and crushed stone aggregate: A performance study

Abstract

This study explores using Induction Furnace Slag (IFS) as aggregate in Quaternary Blended Self-Compacting Concrete (QBSCC) mixes. The experimental work consists of two stages. Stage I focuses on determining the optimal QBSCC mixes, aiming to develop environmentally friendly Self-Compacting Concrete (SCC) by utilizing different types and ratios of cementitious materials. A total of 27 QBSCC mixes were prepared with a reference SCC mix consisting of 100% ordinary Portland cement (OPC), are prepared considering water binder (w/b) ratio of 0.4. The quaternary blended mixes are created by combining OPC, class F Fly Ash (FA), Silica Fume (SF) and Ground Granulated Blast Furnace Slag (GGBFS). The replacement ranges for SF are set between 2.5% and 7.5% in increments of 2.5%, for FA between 10% and 20% in increments of 5%, and GGBFS between 30% and 50% in increments of 10%. In stage II, the optimized QBSCC mixes are further enhanced by incorporating IFS, the properties in the fresh state such as slump flow, V-funnel, L-box, and J-ring tests are conducted for all SCC mixes, all of which comply with the EFNARC guidelines. The mechanical characteristics studied, includes compressive strength (cube and cylinder), split tensile strength (at 3, 7, 28, and 56 days), flexural strength (at 28 and 56 days), elastic modulus, shear strength and pull-out bond strength (at 56 days) are evaluated. It is noted that the hardened properties of SCC mixes containing IFS exhibit slightly higher values compared to crushed stone aggregate SCC mixes. Furthermore, an increase in Supplementary Cementitious Material (SCM) content in QBSCC mixes leads to a decrease in the hardened properties, irrespective of the kind of aggregate used. The QBSCC mixes identified as SCC57.5/42.5, SCC52.5/47.5, and SCC47.5/52.5 are determined to be the preferred blends for producing Self-Compacting Concrete (SCC). Remarkably, Induction Furnace Slag (IFS) can be utilized as both fine and coarse aggregate, completely replacing conventional aggregates, regardless of the content of supplementary cementitious materials (SCM). This finding highlights the notable effectiveness of IFS as a replacement material in SCC production.