วารสารวิชาการเทคโนโลยีอุตสาหกรรม(The Journal Of Industrial Technology)
Abstract
AbstractThis article presents the effect of ordinary Portland cement (OPC) replacement on low calcium fly ash (FAF)and high calcium fly ash (FAC) geopolymer paste. Fly ash was replaced with OPC at the rate of 5, 10 and 15% by weightof binder. Sodium silicate (Na2SiO3) and 10 molar sodium hydroxide (NaOH) solutions were used as the alkaline solutionin the reaction. The Na2SiO3/NaOH ratio of 0.67 and the liquid/binder (L/B) ratio of 0.50 and the curing at ambienttemperature were used for all of mixtures. The results found that the level replacement of OPC increase showed thecompressive strength tended to increased. The compressive strength of low calcium fly ash (FAF) and high calcium flyash (FAC) geopolymer paste at 7 days with 15% OPC replacement were 22 and 34 MPa, respectively. In addition, themicrostructure analysis indicated that the increase of OPC replacement resulted in the addition formation of calciumsilicate hydrate co-exists with the aluminosilicate geopolymer products. This results lead to overall increase in thecompressive strength of fly ash geopolymer products
