| Geopolymers are an innovative ceramic material composed of long chains and networks of inorganic molecules are being used as an alternative to conventional Portland cement for infrastructure construction, replacement of intersection and localized repairs. Some of the advantages of this material is due to its ultra-fast setting time, rapid strength development and the phenomenal reduction in carbon foot print as compared to Portland cement. However, this material is yet to be commercialized due to the variability in its mechanical strength when using flyash from different sources.;In this study aluminosilicate geopolymers with different alkali oxides (feldspars) have been prepared by mixing class F-flyash and alkaline solution. The samples were cured under different experimental conditions and then tested for compressive strength. X-ray diffraction (XRD) and scanning electron microscopy (SEM/EDS) have been used to identify the new phases formed in geopolymeric matrix. In addition, these techniques were used to follow the curing process and the formation of these phases and to map the underlying relationship between the flyash properties and mechanical properties of the geopolymer. |
