High performance aluminosilicate based cementitious materials were produced using calcined gangue as one of the majorraw materials. The gangue was calcined at 500°C. The main constituent was calcined gangue, fly ash and slag, while alkali-silicatesolutions were used as the diagenetic agent. The structure of gangue-containing aluminosilicate based cementitious materials wasstudied by the methods of IR, NMR and SEM. The results show that the mechanical properties are affected by the mass ratio betweenthe gangue, slag and fly ash, the kind of activator and additional salt. For 28-day curing time, the compressive strength of the samplewith a mass proportion of 2:1:1 (gangue: slag: fly ash) is 58.9 MPa, while the compressive strength of the sample containing 80wt%gangue can still be up to 52.3 MPa. The larger K+ favors the formation of large silicate oligomers with which Al(OH)4? prefers to bind.Therefore, in Na-K compounding activator solutions more oligomers exist which result in a stronger compressive strength of alumino-silicate-based cementitious materials than in the case of Na-containing activator. The reasons for this were found through IR and NMRanalysis. Glauber’s salt reduces the 3-day compressive strength of the paste, but increases its 7-day and 28-day compressive strengths.
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