Rishi Khanna
Independent Researcher
India
ABSTRACT
The sustainable construction industry has increasingly adopted supplementary cementitious materials (SCMs) to reduce the environmental impact of Ordinary Portland Cement (OPC). Among these, fly ash and ground granulated blast furnace slag (GGBFS) are widely studied for their pozzolanic and latent hydraulic properties, respectively. This manuscript investigates the combined use of fly ash and slag in green concrete mixes optimized for structural applications circa 2015. A series of mix designs with varying replacement levels (15–45% fly ash and 20–50% slag) were tested for compressive strength, workability, and durability. Statistical Analysis using one-way ANOVA evaluates the significance of strength improvements. Methodology encompasses mix proportioning, casting, curing, and testing per ASTM C109. Results indicate that binary blends with 30% fly ash and 40% slag achieve comparable 28-day compressive strength to control mixes, with a reduction in CO₂ footprint by up to 35%. Research gaps identify long-term durability under aggressive environments and early-age strength trade-offs. The study substantiates that optimized fly ash–slag concretes circa 2015 offer a viable pathway to sustainable construction.
KEYWORDS
Fly ash, Slag, Green concrete, Sustainable construction, Compressive strength, Pozzolanic materials
REFERENCES
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