The slow early strength development of MgO-calcined clay cementitious materials poses significant challenges in meeting industrial requirements, thereby limiting their large-scale application. To address this issue, this study employed 1 wt% of sodium bicarbonate to activate the MgO-calcined clay cementitious materials and compared its effectiveness with that of two commonly used early strength agents: calcium chloride and sodium sulfate. The results demonstrated that sodium bicarbonate promoted strength development more effectively than both calcium chloride and sodium sulfate. This enhanced performance was attributed to the superior ability of sodium bicarbonate to facilitate the dissolution of the Mg(OH)2 surface layer formed during the hydration of MgO. Consequently, the reactivity of MgO was improved, leading to the formation of more hydration products. This study provides a pathway for the activation and application of MgO-calcined clay cementitious materials.

中文翻译：

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通过碳酸氢钠促进 MgO 水化：提高 MgO 煅烧粘土胶凝材料的强度


MgO 煅烧粘土胶凝材料的早期强度发展缓慢，对满足工业要求提出了重大挑战，从而限制了其大规模应用。为了解决这个问题，本研究使用了 1 wt% 的碳酸氢钠来活化 MgO 煅烧粘土胶凝材料，并将其有效性与两种常用的早期强度剂：氯化钙和硫酸钠的有效性进行了比较。结果表明，碳酸氢钠比氯化钙和硫酸钠更有效地促进强度发展。这种增强的性能归因于碳酸氢钠的卓越能力，它能够促进 MgO 水合过程中形成的 Mg（OH）2 表面层的溶解。因此，MgO 的反应性得到改善，导致形成更多的水合产物。本研究为 MgO 煅烧粘土胶凝材料的活化和应用提供了一条途径。