粉煤灰对混凝土抗氯盐侵蚀性能的影响

发布时间：2018-05-28 04:17

本文选题：混凝土耐久性 + 粉煤灰　；参考：《混凝土》2017年07期

【摘要】：利用电通量法、快速迁移法和压汞法试验分析了不同粉煤灰掺量(0、10%、20%、30%、40%)以及不同养护龄期(28、56、90 d)对强度为C55混凝土的电通量、氯离子扩散系数及孔结构的影响;研究了平均孔径与粉煤灰掺量、养护龄期的关系,并以平均孔径为中间变量,得到了氯离子扩散系数和粉煤灰掺量、养护龄期的关系式。研究表明,粉煤灰的掺入可以较好地改善混凝土的抗氯离子扩散性能,该效应在较长养护龄期的情况下尤为明显;对于强度为C55的混凝土,当粉煤灰掺量为30%时,混凝土抗氯盐侵蚀性能最好;粉煤灰的掺入可明显改善混凝土孔结构的分布,增加无害孔和少害孔所占的比例;减小平均孔径和最可几孔径,当粉煤灰掺量在30%时,混凝土具有更优的孔隙结构;氯离子扩散系数的实测值与计算值变化趋势基本相同。
[Abstract]:By means of electric flux method, rapid migration method and mercury injection method, the effects of different fly ash content of 0 ~ (10) and different curing ages on the electric flux, chloride diffusion coefficient and pore structure of C55 concrete were analyzed. The relationship between the average pore size and the amount of fly ash and curing age was studied. The relationship between chloride ion diffusion coefficient, fly ash content and curing age was obtained by taking the average pore size as the intermediate variable. The results show that the mixing of fly ash can improve the chloride diffusion resistance of concrete, especially in the case of long curing age, and for concrete with strength of C55, when the content of fly ash is 30, The concrete has the best resistance to chloride corrosion; the mixing of fly ash can obviously improve the distribution of concrete pore structure, increase the proportion of harmless pore and less harmful pore, reduce the average pore size and the most likely pore size, when the fly ash content is 30%, The concrete has better pore structure, and the measured value of chloride ion diffusion coefficient is basically the same as the calculated value.
【作者单位】：南京工业大学土木工程学院;
【基金】：国家自然科学基金(51308290) 江苏省自然科学基金(BK20130947) 教育部博士点基金新教师类(20133221120004)
【分类号】：TU528

【参考文献】