The effect of additive compound in self-compacting geopolymer mortar on the compressive and flexural strength

Abstract Using geopolymer materials in concrete manufacturing has been found to lead to inconsistent and variable quality, mostly because of its low workability. Further research was undertaken to improve the workability of self-compacting geopolymers by additional examination. This study aims to assess the influence of different additives on the mechanical properties of self-compacting geopolymer concrete, specifically in relation to its compressive and flexural strength. The compressive and flexural strength of geopolymer mortar was assessed after 28 days of curing, during which it was covered with a thin film layer. Cube and beam specimens were used for testing. The findings suggest that the inclusion of additives in the geopolymer mortar yields compressive strength similar to that of conventional mortar, except in cases when extra water is introduced, leading to a decrease in compressive strength compared to traditional mortar. Moreover, the use of additional cement results in a 1.29-fold enhancement in flexural strength when compared to geopolymer mortar.