Sustainable Concrete Using Alccofine, Fly Ash, and Dolomite Powder as Partial Cement Replacements
Abstract: Ordinary Portland Cement (OPC) manufacturing is a major contributor to global carbon dioxide emissions and depletes finite limestone reserves, motivating the search for sustainable partial cement replacements. This study presents an experimental and microstructural investigation of concrete incorporating a ternary blend of supplementary cementitious materials (SCMs)- fly ash, Alccofine 1203, and dolomite powder- as partial replacements for cement. Concrete mixes of grades M30, M40, and M50 were proportioned to their respective target mean strengths, and specimens were cast and cured in water at 27 ? 2 ?C. Compressive strength (150 mm cubes), flexural strength (100 ? 100 ? 500 mm beams under third-point loading), and split tensile strength (150 ? 300 mm cylinders) were evaluated at 7, 28, 56, and 90 days in accordance with IS 516, IS 5816, ASTM C39, ASTM C78, and ASTM C496. Results show a consistent increase in all three strength parameters with curing age and with increasing target grade, with compressive strength gaining 18-20% beyond the 28-day value by 90 days, while flexural and split tensile strength gains over the same period were comparatively modest (7-16%). Split tensile strength remained the lowest of the three properties throughout, typically 6-8% of the compressive strength at 28 days, and the flexural-to-compressive and tensile-to-compressive ratios both decreased as grade increased. Scanning Electron Microscopy (SEM) of the hydrated matrix revealed a visible reduction in calcium hydroxide (portlandite) crystals and the formation of a denser calcium silicate hydrate (C-S-H) gel network in the ternary-blended mixes, consistent with pozzolanic consumption of portlandite and pore refinement. The findings confirm that a synergistic fly ash-Alccofine-dolomite blend can deliver strength development and microstructural densification comparable to, or exceeding, conventional OPC concrete while substituting a portion of cement, supporting its use as a sustainable alternative binder system for structural concrete.
Keywords: Sustainable concrete; Supplementary cementitious materials; Fly ash; Alccofine; Dolomite powder; Compressive strength; Flexural strength; Split tensile strength; Microstructure; SEM analysis
How to Cite?: N. Anusha, Kandru Suresh, "Sustainable Concrete Using Alccofine, Fly Ash, and Dolomite Powder as Partial Cement Replacements", Volume 15 Issue 10, October 2026, International Journal of Science and Research (IJSR), Pages: 95-101, https://www.ijsr.net/getabstract.php?paperid=SR26926161159, DOI: https://dx.doi.org/10.21275/SR26926161159