Optimization on the Alkaline Activator Content of Hybridize Ground Granulated Blast Furnace Slag and High Calcium Wood Ash (GGBS-HCWA) for the Fabrication of Geopolymer Mortar

As concerns about global environmental issue grow, there is an emerging need to replace conventional Ordinary Portland Cement (OPC) as binder matrix in concrete. This study set out to determine the hybridization of two industrial byproducts namely GGBS and HCWA activated with low level of alkaline activator. A total of 16 geopolymeric mortar mixtures were prepared with different GGBS-HCWA ratio and different addition of alkaline activator dosage. All specimens were cured at ambient temperature before subjected to the compressive strength test. The result of the study indicates that highest compressive strength of 33.4 MPa could be achieved for the mortar with GGBS-HCWA-SS hybridization ratio of G70H30S6. Overall, these results point out that the addition of alkaline activator solution significantly increase the compressive strength of geopolymeric mortar produced. The hybridization mixtures of GGBS-HCWA-SS namely G80H20S2, G80H20S4, G80H20S6 and G70H30S6 have great potential to be further investigated for implementation on cementless concrete.