PSI - Issue 70

Shashikant Kumar et al. / Procedia Structural Integrity 70 (2025) 501–508

508

4. Conclusion The SCMs like FA and SF offer significant potential as partial replacements for cement in HVFA-SCC. It is clear that ternary cementitious mixes of FA, SF, and OPC provide considerably greater improvements over ordinary portland cement and substantial advantages over binary blends of SCC. The FA continuously improves the hardened properties of SCC at its later ages, while the SF enhances the SCC's early age strength. These mixes outperform ordinary portland cement concrete in terms of durability. On the basis of material prices, the ternary blend may occasionally be able to compete with ordinary portland cement due to price discrepancies between the separate components. It is feasible to produce SCC by incorporating both SF and HVFA. The addition of these materials enhanced the fresh, hardened, and microstructural properties of the concrete. While the mix exhibited improved hardened and microstructural properties, the inclusion of SF led to a higher T-500 time, reduced slump flow, increased V-funnel time, and a greater J-ring flow. The mechanical properties, as measured in the study, indicated that the inclusion of additional cementitious materials resulted in relatively higher strengths after 56 days. For all the mixes tested, the optimal compressive strength was achieved with 6-8% SF content. SEM pictures of SCC produced with a combined use of HVFA and SF exposed fewer pores, improved viscosity of cement paste, better packing of aggregate, and a thick matrix of mortar. Because ternary blends reduce the production of ettringite and the CH content, SCC with them shown notable improvements in microstructural characteristics. It was discovered that the chemical composition of FA and SF contained a substantial quantity of SiO 2 . The amorphous C-S-H gel was created when this silicate reacted with free Ca(OH) 2 during the OPC chemical reaction period. Consequently, the amount of Ca(OH) 2 , which is hazardous to concrete, dropped. The HVFA and SF may be utilized in conjunction to partial replacement of cement in further research pertaining to shrinkage behavior, corrosion studies, performance in harsh environments, performance at elevated temperatures, etc. References Bogue, R. H., & Lerch, W., 1934. Hydration of Portland Cement Compounds. Industrial and Engineering Chemistry. Dadsetan, S., & Bai, J., 2017. Mechanical and microstructural properties of self-compacting concrete blended with metakaolin, ground granulated blast-furnace slag and fly ash. Construction and Building Materials, 146, 658 – 667. Demirboǧa, R. , 2003. Influence of mineral admixtures on thermal conductivity and compressive strength of mortar. Energy and Buildings, 35, 189 – 192. Huang, C. H., Lin, S. K., Chang, C. S., & Chen, H. J., 2013. 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