脱硫石膏-粉煤灰复合胶凝材料的力学性能研究

Study of the Mechanical Properties of FGD Fly Ash Composite Cementitious Material

研究了脱硫石膏-粉煤灰复合胶凝材料的力学性能及微观结构。结果表明:磨细粉煤灰较原样粉煤灰对脱硫石膏的力学性能有较大的改善,掺加20%磨细粉煤灰可以得到较高强度的脱硫石膏-粉煤灰复合胶凝材料。由超景深显微镜和XRD分析推断出:粉煤灰的滚珠效应和骨架作用改善了脱硫石膏的力学性能,但在干燥环境下,粉煤灰的水化反应得不到有效进行,复合胶凝材料的强度主要来源于水化产物CaSO4.2H2O。

This paper studied the mechanical properties and microstructurc of FGD gypsum-fly ash composite cementitious material. The results showed that mechanical performance of FGD gypsum was more significantly improved by adding ground fly ash than original one and higher strength of FGD gypsum-fly ash composite cementitious material could be obtained by mixing 20% ground fly ash. By means of super depth field microscope and XRD, we could infer that the fly ash improved mechanical properties of FGD gypsum owing to its ball bearing and skeleton effect. The hydration reaction of fly ash could not progress in dry surroundings, the strength of composite cementitious material mainly come from the hydration body CaSO4·H2O.