Geopolymer Mortar
Abstract
Geopolymer Mortar The cement industry accounts for about 7% of all CO2 emissions caused by humans. Therefore, it is necessary to find another material in order to support sustainable material. An alternative way is replacing cement material with alternative material as fly ash. Fly ash as binder need to be added alkaline activator in the form of sodium silicate (Na2SiO3) or potassium silicate (K2SiO3) and sodium hydroxide (NaOH) or potassium hydroxide (KOH).
The experimental result of fresh mortar reported that the molarity of NaOH affect the slump flow and setting time, higher of NaOH produces the smaller value of slump and the faster time of setting. The experimental of density results reported that the increase of specific gravity when the molarity of NaOH increased.
Conclusion
The comprehensive experimental test results and analysis of various geopolymer mixtures in this study can be summarized below:
- The addition of alkali activator (NaOH) with bentonite was not effective in the initiation of geopolymerisation reaction at ordinary room temperature and showed a marked improved setting when cured in hot air oven at 100o C.
- It can be observed that the binary blends containing flyash (20%) and lime (10%) in bentonite with the addition of alkali at 8M provided early setting properties through the initiation of geopolymerisation.
- The time lag (final – initial setting time) for all the binary mixtures showed a consistent reduction in setting time and shows that the Si/Al ratio present in the constituents for the initiation of geopolymerisation reaction.
