Synergistic effects of quaternary supplementary cementitious blends in high-performance self-compacting concrete

This study examines the potential of high-volume Supplementary Cementitious Materials (SCMs) in advancing sustainable, low-cost, low-carbon Self-Compacting Concrete (SCC) through a quaternary binder design. Ground Granulated Blast Furnace Slag (GGBFS), Class F Fly Ash (FA), and Silica Fume (SF) were incorporated as partial replacements for Ordinary Portland Cement (OPC) to formulate Quaternary Blended Self-Compacting Concrete (QBSCC). Twenty-eight mixes were developed, including one control and twenty-seven quaternary blends, at a constant water-to-binder ratio of 0.4. The SCMs substitution ranged from 42.5% to 77.5%, with GGBFS serving as the dominant component. Rheological compatibility of the quaternary binder composition and superplasticizer dosage was assessed using mini-slump and Marsh cone tests. Fresh-state properties of QBSCC were evaluated through slump flow, L-box, V-funnel, and J-ring tests. Mechanical performance was characterized by compressive, split tensile, and flexural strength tests, and durability was assessed using Rapid Chloride Permeability and electrical resistivity methods. Economic and environmental impacts were quantified via cost analysis and carbon footprint assessment. The results demonstrate that all QBSCC mixtures exhibited superior flowability compared to the reference mix. Compressive strength improved modestly (1– 4%) at 28 days for mixes with 42.5–50% SCMs replacement and more substantially (up to 7%) at 56 days for 42.5–57.5% replacements. Enhancements in tensile and flexural strength followed similar trends. Durability was significantly improved, evidenced by reduced chloride permeability and elevated resistivity. Additionally, QBSCC achieved cost savings of 18– 43% and carbon emission reductions of 38–70%. These outcomes highlight the efficacy of quaternary SCMs systems in producing high-performance, low-carbon SCC with demonstrable technical, economic, and environmental advantages.