MECHANICAL AND DURABILITY PROPERTIES OF FLY ASH GEOPOLYMER CONCRETE – A REVIEW

Abstract

al., 2018). A study conducted by Wang et al. (2020) on the impact of different Si/Al ratios on the occurrence of efflorescence in GPC. The study examined several ratios, including 0.5, 1, 1.5, 2, and 2.5, which were achieved by incorporating bauxite into fly ash. The findings revealed that raising the Si/Al ratio to 1.5 reduced the level of efflorescence. However, when the ratio was increased beyond 1.5, the efflorescence levels began to rise again. The optimal resistance to efflorescence was observed at a Si/Al ratio of 1.5, where the concrete exhibited the smallest pore volume of 0.017 cm3/g, smallest pore size of 6.21 nm, and the highest level of aluminum tetrahedra. These parameters were crucial in regulating the migration of alkalis, resulting in a reduction in the degree of efflorescence.