Abstract Previous studies have shown that fine lightweight aggregate (FLWAs) may be a possible solution for ASR mitigation. However, the mechanisms of mitigation have not yet been fully elucidated. This study investigated how three commonly used FLWAs, expanded slate, shale, and clay can mitigate ASR in concrete using the accelerated mortar bar test (AMBT), concrete prism test (CPT), pore solution analysis and scanning electron microscope (SEM) analysis. The AMBT and CPT results showed that expanded clay was the most effective in reducing the expansion caused by ASR. Pore solution analysis showed that FLWAs, especially expanded shale and clay can reduce the alkalinity as well as increase aluminum content in the pore solution. SEM analysis revealed that infilling reaction products formed in the pores of the FLWAs, whose composition was closer to C-A-S-H, rather than alkali-silica reaction product.

中文翻译：

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细轻集料减缓碱硅反应的机理研究

摘要 先前的研究表明，细轻骨料 (FLWA) 可能是缓解 ASR 的可能解决方案。然而，缓解机制尚未完全阐明。本研究使用加速砂浆棒试验 (AMBT)、混凝土棱柱试验 (CPT)、孔隙溶液分析和扫描电子显微镜 (SEM) 分析，研究了三种常用的 FLWA，膨胀板岩、页岩和粘土如何减轻混凝土中的 ASR。AMBT 和 CPT 结果表明膨胀粘土在减少由 ASR 引起的膨胀方面最有效。孔隙溶液分析表明，FLWAs，特别是膨胀页岩和粘土可以降低孔隙溶液中的碱度并增加铝含量。SEM 分析表明，在 FLWA 的孔隙中形成了填充反应产物，