Hydration study of cement mixtures containing fly ash of different structure of glassy phase

• 作 者: TkaczewskaEwelina;Ma(l)olepszyJan;
• 机 构: Department of Building Materials Technology, Faculty of Materials Science and Ceramics, AGH Universi
• 出 处: The 14th International Congress on the Chemistry of Cement (
• 发表日期: 2015年期

　　Impact of fly ash glass structure on pozzolanic activity of this material and hydration process of blended cement was studied.The three glass samples of various Al2O3/(Na2O+K2O+2CaO) ratio 0.77, 2.52 and 4.02 were synthesized.The MIR and 27Al MAS-NMR spectroscopic studies confirmed presence of Si-O and Al-O bonds in glasses, but in glass of Al/(Na+K+2Ca) below 1 the Al ions occurred only in tetrahedra AlO4, whereas in glass of this ration above 1 also in octahedra AlO6.Glass, in which the Al ions are presented in the 4-and 6-fold coordination shows better pozzolanic properties than glass cotraining only tetrahedral aluminum framework.Model fly ash samples are prepared by mixing synthetic glass, synthetic mullite and SiO2.Results indicate that fly ash of higher content of AlO6 units in glass has positive influence on the cement hydration process and mechanical properties of cement mortar).