Abstract Calcium aluminosilicate (CAS) glasses are the main reactive component in supplementary cementitious materials such as fly ashes and slags, which may also include significant amounts of magnesium. Eighteen CAS glasses have been synthesized in six series with 0, 25, and 50 mol% of Ca substituted by Mg. Their structure, pozzolanic reactivity and impact on Portland cement hydration are investigated by 29Si and 27Al NMR spectroscopy and TGA analysis. The aluminosilicate network is only slightly affected by the Mg for Ca substitution, although an increased distortion of the network is observed, which is ascribed to a lowering of the Mg coordination state relative to Ca. The glass reactivity is mainly governed by the network depolymerization, which increases with the MgO + CaO content, with Mg substitution only having a minor impact. Increasing Mg contents in the glasses lead to OH-hydrotalcite formation and a smaller fraction of Al incorporated in the C-A-S-H phase.

中文翻译：

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镁取代对铝硅酸钙 (CaO-Al2O3-SiO2) 玻璃结构和火山灰反应性的影响

摘要 铝硅酸钙 (CAS) 玻璃是粉煤灰和矿渣等辅助胶凝材料中的主要反应成分，其中还可能含有大量的镁。已经合成了 6 个系列的 18 种 CAS 玻璃，其中 0、25 和 50 mol% 的 Ca 被 Mg 取代。通过 29Si 和 27Al NMR 光谱和 TGA 分析研究了它们的结构、火山灰反应性和对硅酸盐水泥水化的影响。铝硅酸盐网络仅受 Mg 替代 Ca 的轻微影响，尽管观察到网络畸变增加，这归因于 Mg 配位状态相对于 Ca 的降低。玻璃反应性主要受网络解聚控制，随着 MgO + CaO 含量的增加而增加，而 Mg 取代的影响很小。