Abstract: “This study investigated the effect of four different amounts of alkaline solution (240, 270, 390 and 435 ml) used in the production of metakaolin and fly ash-based geopolymer mortar on sample properties. In the preparation of geopolymer mortars, metakaolin obtained by the sintering at 1000 °C of kaolin clay and fly ash obtained from Kütahya Seyit Ömer (Turkey) thermal power plant was used. Geopolymer mortars were cast into 40x40x160 mm molds and cured for 5 h at 80 oC in a laboratory-type oven. The curing process of the samples was completed, and they were subjected to physical and mechanical tests at the end of the 7th day following their production. Consequently, it was determined that the ideal amount of alkali solution in the preparation of the geopolymer mortar samples was 270 ml. In addition, the flexural and compressive strength values of the geopolymer mortars produced using 270 ml alkaline solution were 4.9 MPa and 21.8 MPa, respectively.”

Keywords: fly ash, metakaolin, alkaline solution, geopolymer, mortar.