越南粉煤灰对混凝土的物理性能、耐久性和钢铁腐蚀概 率的影响

保罗 ·特, 钦凡 兰伯, 广 阮
越南土木工程系

摘要

越南粉煤灰以 10%、20%和 40%的比例作为普通硅酸盐水泥的部分替代品，而三组的水胶比分别保持在 0.42、 0.5 和 0.55。所有混合物的抗压强度被测定到 90 天。粉煤灰混凝土的耐酸性通过浸泡在 10% H2SO4 溶液中的 100× 100×100mm3 立方体的质量损失和抗压强度损失来检验。通过测量尺寸为 100×100×500mm3 的梁内钢筋的半电池 电位来评估粉煤灰混凝土中钢筋的腐蚀概率，并确定这些梁在 5%的氯化钠溶液中浸泡 300 天后的抗弯强度。结果表 明，粉煤灰混凝土的抗压强度在早期阶段会降低，但随着混凝土继续水化而增加。粉煤灰增加了混凝土的耐硫酸性。 粉煤灰的添加对减少混凝土中钢材腐蚀概率的风险只有有限的作用。在 5%的氯化钠溶液中浸泡 300 天后，10%和 20% 的粉煤灰加固的混凝土梁的承载力要高于对照组。

关键词

混凝土；粉煤灰；工作性；抗压强度

参考

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