大掺量粉煤灰对混凝土渗透性的影响

以粉煤灰代替３０％的水泥，在水胶比为０．３０、０．３３、０．３６及０．３９的情况下，分别试验了用水量及胶凝材料用量变化下混凝土的强度和渗透性。试验结果表明，与不掺粉煤灰的混凝土比较，掺粉煤灰混凝土的渗透性都明显降低，３０天龄期时最大可降低至５０．７％，７０天时可降低至２２．３％；为了获得较低的渗透性而采取较低的水胶比时，不掺粉煤灰的混凝土应用降低用水量的办法有利，掺粉煤灰的混凝土用提高总胶凝材料用量的办法更好

Effect of Large Amount of Fly Ash on Permeability of Concrete

The strength and permeability of various pure cement concrete and fly ash concrete are tested, in which the content of water or binding materials changes with water binding materials ratio of 0.30, 0.33, 0.36 or 0.39, and the fly ash content in fly ash concrete is 30% of its total binding materials by weight. Experiments show that the permeability of fly ash concrete is significantly lower than that of pure cement concrete, with 50.7% and 22.3% of the later in 30 and 70 days of age, and that when water binding materials ratio is lowered in order to get lower permeability, reducing water content is better than increasing binding materials for pure cement concrete, and increasing binding materials is better for fly ash concrete.