复合腋凝材料对混凝土抗压强度的影响

Influence of compound mineral admixture on concrete compressive strength

以不同比例的粉煤灰、矿粉、天然矿物和活化剂，进行双掺、三掺和四掺配制成复合胶凝材料，并按不同比例等量替代水泥配制C30混凝土（水胶比为0．49），然后测定各试样混凝土拌合物的坍落度以及7d，28d，60d的混凝土抗压强度。结果表明：（1）以粉煤灰、矿粉、天然矿物和活化剂四掺配的复合胶凝材料35％～40％等量替代水泥，其拌合物的坍落度比基准混凝土提高15％-33％，其混凝土的60d龄期抗压强度可比基准混凝土提高9％-14％以上；（2）试验条件下最佳的复合胶凝材料配料方案为：粉煤灰30％－50％、矿渣30％－60％、天然矿物5％－10％、活化剂为5％－10％。

Fly ashes, grounded blast furnace slag, natural minerals and activators were used to develop compound mineral admixtures by mixing two of them, three of them and four of them. Then the compound mineral admixtures replaced partly of cement to made C30 grade concrete whose compressive strength at 7 d, 28 d and 60d and slumps were tested and studied. The results show as follows：（1） when the compound mineral admixtures which were produced with fly ashes, grounded blast furnace slag ,natural minerals and activators replaced 35%-40% of cement, the slump of this concrete increased at 15%-33%and the 60 d compressive strength increased at 9%-14% compared to the sample concrete; （2） the best proportion scheme of compound mineral admixtures was 30%-50% flv ashes. 30%-60% arounded blast furnace slag. 5%-10% natural minerals and 5%-10% activators.