The Basic Mechanical Properties of the Fluidised Bed Combustion Fly Ash-Based Geopolymer

The main goal of the research was to check the influence of different factors on the mechanical behaviour of the fluidised bed combustion (FBC) fly ash-based geopolymer. Tests have shown that the increasing the proportion of sodium silicate to sodium hydroxide causes a decrease of compressive strength and an increase of flexural strength. The addition of aggregate significantly increased flexural strength but decreases compressive strength. Samples cured at higher temperatures obtained higher strength. Finally, it was concluded that taking into account the mechanical behaviour, FBC fly ash-based geopolymer can be treated as an alternative building material; however, its strength is lower than a metakaolin-based geopolymer made of the same mixture composition.