Effect of FA and GGBFS on the properties of geopolymer morter

Various amounts of natural resources are consumed to manufacture ordinary Portland cement which causes considerable environmental problems for its production. A new technological process called geopolymerization provides an innovative solution in this issue. In addition to potentially reducing carbon emissions, geopolymers can be synthesized with many industrial waste products or natural pozzolans such as fly ash, ground granulated blast furnace slag. In the present study, the experimental test of different proportions of GGBFS and FA in the binder on mechanical and durability properties of geopolymer concrete. To achieve this goal, GGBFS has been used as cement replecement material due to its own strength, while fly ash has been used as a pozzolanic material to enhance the physical, chemical and mechanical propeties of concrete (Swamy, 1986). The geopolymer binder is a mixture contains resource material and alkali activator. Ten mixes have been tested; each mixture has different proportion of FA and GGBFS. It can be concluded that geopolymer concrete with high percentage of GGBFS gain high compressive and tensile strength compared with Geopolymer with high FA. Compressive strength of mix1 ( 90% FA and 10% GGBFS ) is 39.15 Mpa at 7 days age, compressive strength of mix10 ( 90% GGBFS and 10% FA) is 75.17 Mpa at 7days age. In addition, the duribility of geopolymer mortar, made of these mixes, was also studied, using water sorptivity test. The test results indicated that geopolymer with high percentage of GGBFS has less sorptivity compared with geopolymer with high percentage of FA.