Optimizing Alkaline Molarity for Enhanced Compressive Strength in Geopolymer Concrete Blended with Equal Proportions of GGBS and Fly Ash
DOI:
https://doi.org/10.5281/weyn2p11Keywords:
Geopolymer Concrete, Compressive Strength, GGBS and Fly Ash, Alkaline Molarity and M25 Grade ConcreteAbstract
This experimental study investigates the impact of alkaline molarity on the compressive strength of geopolymer concrete (GPC) designed to be M25 grade. The GPC mix contained 50% Ground Granulated Blast Furnace Slag (GGBS) and 50% Fly Ash as the binder. Alkaline activator solutions were formulated with molarities of 8M, 10M, 12M, 14M and 16M to produce the geopolymer matrix. Concrete specimens were tested for compressive strength and flexural strength under the standard curing times. The findings show that compressive strength increased with molarity to the optimum alkaline molarity level after which compressive strength plateaued, and slightly decreased. 12M ulated a compressive strength higher than all other variations therefore the most efficient molarity for structural grade geopolymer concrete strength. This investigation offers some valuable information on the optimized alkaline activator concentration for sustainable concrete applications.
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