不同养护温度下磨细粉煤灰的反应活性分析

Reactivity analysis of ground fly ash under different curing temperature condition

分别使用粉磨前后的粉煤灰制备水泥浆体试样,对不同养护温度下试样的抗压强度和粉煤灰反应程度进行分析,并使用XRD物相分析和热重分析研究其作用机理。结果表明:由于在粉磨过程中部分球形颗粒被破坏,磨细粉煤灰在水泥浆体中消耗更多氢氧化钙而产生强度相,其反应程度随养护温度提高而增加最多;使用磨细粉煤灰制备的水泥浆体各龄期抗压强度均高于其他粉煤灰,温度升高时其强度上升幅度最大,当养护温度为80℃时,掺磨细粉煤灰试样在各龄期强度可达到纯水泥浆体的80%以上。

Fly ash before and after grinding was used to prepare cement paste samples,and the compressive strength and reaction degree of fly ash were analyzed under different curing temperatures,and the mechanism of action was studied by XRD phase analysis and thermogravimetric analysis.The results show that some spherical particles are destroyed during the grinding process,and the strength phase of the pulverized fly ash is generated by consuming more calcium hydroxide in the cement paste.The reaction degree of the strength phase increases the most with the increase of curing temperature.The compressive strength of the cement paste prepared with ground fly ash is higher than that of other fly ash at each age,and the strength increases the most when the temperature increases.When the curing temperature is 80℃,the strength of the sample mixed with ground fly ash can reach more than 80% of that of the pure cement paste at each age.