The aim of this study is to compare the mechanical and physical properties different geopolymer mortars made with granulated blast furnace slag as a source material, NaOH (8 M) activating solution, three types fine aggregates (air-cooled slag, biomass bottom ashes, silica sand). samples were an aggregate/geopolymer ratio 3/1, (density mercury intrusion porosimetry), (compressive flexural streng...