Effect of molarity of sodium hydroxide and molar ratio of alkaline activator solution on the strength development of geopolymer concrete
V Srinivasa Reddy, K. V. Krishna, M V Seshagiri Rao, S. Shrihari
Abstract
In the current study, effect of SiO 2 /Na 2 O ratio in Sodium silicate (Na 2 SiO 3 ) solution, Na 2 SiO 3 /NaOH ratio and molarity of NaOH on the compressive strength of geopolymer concrete. A geopolymer mix design is formulated with various mixes are casted with alkali activator solution (AAS) / fly ash (FA) =0.5 and constant fly ash content. The molar ratio of SiO 2 /Na 2 O in Na 2 SiO 3 solution is altered from 1.50 to 3.00 for different ratios of Na 2 SiO 3 /NaOH (2.0, 2.5 and 3.0) and also for various molarities of NaOH (8M,10M,12M,14M,16M and 18M) are studied for their synergic effect on the compressive strength of geopolymer concrete. Results highlighted that the 16M NaOH yields high compressive strength when SiO 2 /Na 2 O in Na 2 SiO 3 solution is around 2.00 to 2.40 and Na 2 SiO 3 /NaOH=2.5.