粉煤灰活性骨料在砂浆中的水化特性研究

Research on Hydration Characteristics of Fly Ash Active Aggregate in Mortar

通过粉煤灰水化试验量化其水化程度,研究粉煤灰细骨料砂浆在不同养护温度、粉煤灰替代率、养护龄期下的力学性能、非蒸发水含量和粉煤灰水化程度。结果表明,20℃养护下,粉煤灰水化程度随替代率增加而降低;50℃养护下,试样在1 d时粉煤灰临界替代率为35%,小于35%以灰效应为主,大于35%以微集料效应为主;80℃养护明显提高试样1 d龄期粉煤灰水化程度及非蒸发水含量,但是不利于长期力学性能发展。

The hydration degree was quantified through fly ash hydration experiment,the mechanical properties,non-evaporating water content and the degree of fly ash hydration of the fly ash fine aggregate mortar under different curing temperatures,replacement rates,and curing ages were systematically studied.The results show that the hydration degree of fly ash cured at 20℃decreases with the increase of the replacement rate;cured at 50℃,the critical replacement rate of fly ash at 1 d is 35%,less than 35%,the pozzolanic effect is the main factor;more than 35%,the micro-aggregate effect is the main factor;cured at 80℃,the hydration degree of fly ash and the non-evaporating water content of sample at 1 d are improred obviously,but it is not conducive to the development of long-term mechanical properties.