不同水胶比下矿渣粉与粉煤灰对混凝土强度及抗氯离子渗透性能的影响

Influence of slag and fly ash on concrete strength and resistance to chloride ion penetration performance under different water-cement ratio

在水胶比分别为0.60、0.50、0.28三种情况下,研究了矿渣粉和粉煤灰单掺及复掺对混凝土强度及抗氯离子渗透性能的影响。结果表明:无论水胶比大小,Ⅱ级粉煤灰均不能等量取代P·O42.5R级水泥,应超量取代,且水胶比越大,超量系数越大;在研究的掺量范围内,S95矿渣粉可等量取代P·042.5R级水泥,且会增加混凝土强度。在合适掺量范围内,无论水胶比高低,无论混凝土强度增大或减小,矿渣粉和粉煤灰均可提高混凝土抗氯离子渗透能力,但当掺量接近时,矿渣粉对提高混凝土抗氯离子渗透性的能力远大于粉煤灰;颗粒多为球形微珠的粉煤灰掺入混凝土中,其对抗渗性的贡献大于对强度的贡献。

At the water-binder ratio being 0.60,0.50 and 0.28 respectively, the influences of slag and fly ash single-used or compounded on the compressive strength and resistance to chloride ion penetration of concrete were investigated.The results show that no matter how much the water-binder ratio, fly ash of 2nd grade can not replace equivalently P-O 42.5R cement, while should replace excessively, and the replacing excessive coefficient should be enhanced with the increase of water-binder ratio.Under the scope of amount used in the paper,S95 slag can replace equivalently P ·O 42.5R cement, and can increase the strength of concrete.Under the proper scope of amount used,no matter how much the water-binder ratio and the strength of concrete,both slag and fly ash can improve the resistance to chloride ion penetration of concrete, and the a- bility of slag improving the resistance to chloride ion penetration is much more than that of fly ash, while the latter with many spherical particles contributes to the impermeability more than to the strength of concrete.