Abstract In this work, the degradation mechanisms of alkali-activated slag (AAS), prepared with various activator compositions, exposed to 5% Na2SO4 and MgSO4 solutions are studied. The results show that upon Na2SO4 attack, little ettringite formation and compositional alteration occur in AAS with little length expansion. However, upon MgSO4 attack, brucite, gypsum, and magnesium-aluminosilicate-hydrate (M-A-S-H) are observed in altered layers of hardened AAS pastes. The sulfate-activated slag shows a weaker resistance against MgSO4 attack than NaOH- and Na2CO3-counterparts due to a lower pH value in pore solution and thus absence of brucite protective layer. The reacted products in hardened AAS pastes have a high capacity against dealumination in sulfate environments, contributing to superior sulfate resistance over traditional ordinary Portland cement (OPC).

中文翻译：

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硫酸盐侵蚀碱活化渣的机理：活化剂成分的作用

摘要 在这项工作中，研究了用各种活化剂组合物制备的碱活化炉渣 (AAS) 暴露于 5% Na2SO4 和 MgSO4 溶液中的降解机制。结果表明，在 Na2SO4 攻击下，AAS 中几乎没有钙矾石形成和成分改变，长度膨胀很小。然而，在 MgSO4 侵蚀下，水镁石、石膏和镁-铝硅酸盐-水合物 (MASH) 在硬化 AAS 糊剂的改变层中观察到。由于孔隙溶液中的 pH 值较低，因此没有水镁石保护层，硫酸盐活化炉渣对 MgSO4 侵蚀的抵抗力弱于 NaOH 和 Na2CO3 对应物。硬化 AAS 糊中的反应产物在硫酸盐环境中具有很高的抗脱铝能力，