Production geopolymers by Portland cement: Designing the main parameters’ effects on compressive strength by Taguchi method

In the present study, Taguchi method was utilized to design compressive strength tests of geopolymers produced by Portland cement as aluminosilicate source. Six main factors including NaOH concentration, water glass to NaOH weight ratio, alkali activator to cement weight ratio, oven curing temperature, oven curing time and water curing regime each at four levels were considered for designing. A total of 32 experiments were conducted according to the L32 array proposed by the method. ANOVA analysis of the experimental results suggested a specimen with NaOH concentration of 14 M, water glass to NaOH weight ratio equals to 1, alkali activator to cement weight ratio of 0.42, and curing at room temperature for 28 days to acquire the highest strength (43.1 ± 3.0 MPa) in the considered procedure. The results indicated that compressive strength of Portland cement-based geopolymers could be suitably designed by Taguchi method.

► Production of geopolymers by ordinary Portland cement.
► Taguchi method for designing high strength geopolymers.
► Optimizing the key parameters affecting compressive strength by ANOVA.