The microstructure and durability of fly ash-based geopolymer concrete: A review

Fly ash-based geopolymer concrete (FABGC) is a type of environment-friendly building material that displays remarkable mechanical properties and durability. It has the potential for extensive application in the field of civil engineering. This paper considers the related research on the microstructure and durability of FABGC to systematically summarize the results on its alkali-activated reaction, pore structure, and interface characteristics. The degradation mechanisms of FABGC in various corrosive environments are analyzed, and the factors that affect its microstructure and durability are discussed. It is observed that aluminosilicate gel produced by the alkali-activated process of FABGC has an optimizing effect on the pore structure and interfacial transition zone. An effective development of the microstructure can improve the durability of FABGC to a certain extent. At present, there is no consensus on the research conclusions on the microstructure and durability of FABGC. Therefore, further research is required.