Mechanical properties of class C and F fly ash geopolymer mortars

Mechanical properties of geopolymer mortar made with class F fly ash and class C fly ash are evaluated and compared in this paper. Fly ashes were activated with a combined NaOH and Na2SiO3 alkali solution, and their strength development was observed during one year. It was observed that compressive strength values were between 10.22 and 15.83 MPa for geopolymer mortar mixtures made with class C fly ash. The values of up to 56.44 MPa were obtained for geopolymer made with class F fly ash