Development of a new type of fly ash based geopolymer concrete

The main aim of this study is to determine the optimum mix proportion for a geopolymer concrete for different compressive strengths. This study employed the statistical analysis to find the best fit equation predicts compressive strength of geopolymer concrete from mixture proportion, where the compressive strength is one of the desired and required properties of hardened concrete. The main concept of finding the equation is derived from the feret model, all the factors that effects on the compressive strength of geopolymer concrete and related to the ingredient materials are listed. A regression analysis was done to new model to find the empirical constant of the best fit equation with a highest coefficient of determination R2 = 0.943 and lowest loss function expressed by residual mean squares. For geopolymer concrete at 7 day age was accomplished 85-90 % rate from compressive strength. When water-to-geopolymer binder ratio between 0.16 and 0.24, as the mix was very dry and not workable. When water- to-geopolymer binder ratio between 0.24 and 0.27, as the mix was very viscous and takes more time for mixing. When water-togeopolymer binder ratio between 0.27 and 0.33, as the mix was cohesive and viscous but flow slowly for long time. When water-to-geopolymer binder ratio between 0.33 and 0.40, as the geopolymer concrete mix was spread just like a self-compacting concrete. The rate of increment in compressive quality is fast amid the initial 24 hour of curing time, past 24 hour the pickup in quality is just direct. Statistical analysis showed that the new model is applicable to geopolymer concrete. The developed equation was validated with the experimental results.