焙烧水滑石对水泥-粉煤灰胶凝材料水化及力学性能的影响

Effect of Calcined Hydrotalcite on Hydration and Mechanical Strength of Cement-Fly Ash Cementitious Material

通过改变粉煤灰掺量,观察了焙烧水滑石增强的胶凝材料力学性能、水化及微观结构特性。抗压强度测试表明,焙烧水滑石能极大提高水泥-粉煤灰砂浆抗压强度。通过X射线衍射及综合热分析实验对硬化水泥浆体相组成进行了测试,结果显示焙烧水滑石能促进水泥-粉煤灰胶凝材料水化,进而提高了水化产物含量。通过扫描电子显微镜观察到,焙烧水滑石能促进粉煤灰溶解,且其成核作用有利于水化产物的生成。

The mechanical properties,hydration process and microstructure characteristics of the calcined hydrotalcite modified cementitious material at different fly ash contents were analyzed.Based on the results by the compressive strength test calcined hydrotalcite can greatly improve the compressive strength of cement-fly ash mortar.The phase composition of hardened cement paste was characterized by X-ray diffractionand and thermogravimetric analysis.The results show that calcined hydrotalcite can promote the hydration of cement-fly ash cementitious materials,thereby increasing the content of hydration products.It is incidiacted that calcined hydrotalcite can accelerate the dissolution of fly ash,and its nucleation effect is beneficial to the formation of hydration products.