水泥-粉煤灰复合胶凝材料水化程度的研究

Research on Hydration Degree of Cement-Fly Ash Complex Binders

通过化学结合水量和粉煤灰反应程度的测定,研究了水泥-粉煤灰复合胶凝材料的水化程度.结果表明:粉煤灰的掺入降低了复合胶凝材料的总水化程度,但促进了复合胶凝材料中水泥的水化程度;粉煤灰掺量越大,粉煤灰自身的反应程度越低,水泥水化的程度越高;高温养护对早期复合胶凝材料总水化程度以及粉煤灰的反应程度均有显著的提高作用,但却阻碍了后期复合胶凝材料总水化程度的进一步提升;水胶比对各水化程度趋势的影响较小;90 d粉煤灰反应程度的突增降低了复合胶凝材料中水泥水化程度相对指数,水泥水化对于复合胶凝材料化学结合水量的贡献更多体现在水化早期(28 d前),而粉煤灰的贡献则体现在水化后期(28 d后).

The hydration degree of cement-fly ash complex binders were studied by determining the chemically combined water content and the reaction degree of fly ash. The results show that the incorporation of fly ash decreases the total hydration degree of complex binders, but at the same time, promotes the hydration degree of cement in complex binders. The higher the content of fly ash is, the lower the reaction degree of itself is, whereas the higher the hydration degree of cement is. Curing at high temperature plays a significant role in the advancement of total hydration degree of complex binders in the early stage, and also increases the reaction degree of fly ash, but thwarts the further enhancement of total hydration degree in the late stage. The influence of water-binder ratio on the tendency of various hydration degree is unconspicuous. The uprush of the reaction degree of fly ash at 90 d lowers the relative index of hydration degree of cement in complex binders, which means that the effect of hydration of cement on the chemically combined water content of complex binders occurs mainly within 28 d, but the effect of fly ash occurs in the late hydration age.