Effect of binder composition and alkaline content on the mechanical strength of alkali-activated mortar

Abstract

The research presented here applies a material system including fly ash and blast furnace slag to create an environmentally friendly geopolymer binder to replace traditional cement. The activator used is anhydrous sodium metasilicate pentahydrate and the fly ash/blast furnace slag content is 30%, 40% and 50%; Na2O ratio was investigated at levels 5.0, 5.5 and 6.0. The effects of the above parameters were evaluated through the changes in compressive and flexural strengths of mortar samples at 3, 7, 14, 28, 56 and 91 days old, comparing the samples with cement mortar. traditional bamboo shoots. Geopolymer mortar samples are cured at room temperature and do not use curing water or other heating methods. Experimental results showed that the geopolymer mortar samples had the development of compressive and flexural strength after 7 days of age and achieved values equivalent to the control cement mortar samples. In addition, when the ratio of Na2O used is 5.0, the fly ash/blast furnace slag content of 50/50 will achieve the optimal compressive and bending strength values.