Physico-Chemical and Mechanical Properties of Geopolymer Materials

Abstract

Physico-chemical and mechanical properties of geopolymer materials(cement, mortar, and concrete) were studied. Various mixes are prepared using different liquid/solid ratios (L/S) by weight. Sodium hydroxide pellets (SH) and commercial sodium silicate liquid (SSL) are used as an activator which is dissolved in the mixing water. The hydration characteristics of the different mixes have been tested via determination of bulk density, total porosity, combined water, compressive strength, and XRD analysis at different time intervals from 1 up to 180 days in water. The results showed that the combined water content of the geopolymer materials gradually increases up to 180 days in all mixes. The bulk density increases while the total porosity decreases, as a result of the chemical reaction (geopolymerization process) with formation of new products fill the pores. The compressive strength also increases up to 180 days in all mixes. The data show that SSF1 (95% GGBFS+5 % SF) activated by (24.4% by wt. SSL, and 4 M SH), S3 (100 % GGBFS) activated by (21.7% by wt. SSL, and 4 M SH), and SMK1 (50 % GGBFS+50 % MK) activated by (31.8 % by wt. SSL, and 4 M SH) all in 95% R.H conditions are the most appropriate binding materials (geopolymer pastes) that have good different properties. GM 3 (100 % GGBFS) with a standard sand show the most appropriate mortar mix in different properties.GP Conc. 4 (100 % GGBFS) with a standard sand, and dolomite aggregate in 95% R.H showed the most appropriate concrete mix in different properties, that can be used as alternative building material to the ordinary Portland concrete.