SEM测试技术在全级配混凝土长龄期碱活性试验研究中的应用

为宏观及微观全面系统地掌握混凝土膨胀劣化特性,在国内某大型水电站砂岩骨料碱活性研究的基础上,充分考虑工程实际需要,开展了全级配大体积混凝土碱骨料反应长龄期模拟试验。运用SEM测试技术结合已有碱骨料反应评估体系进行了骨料碱活性抑制效果长期有效性研究。研究结果表明,将SEM测试技术运用于某水电站全级配混凝土碱活性长龄期测试,能明显观测到发生碱活性反应骨料界面的特征反应产物,可半定量了解其碱活性反应程度,预测混凝土劣化趋势。

Application of SEM to the Test on Aggregate Alkali Activity of Fully-graded Long-age Concrete

In order to understand the expansion and deterioration of concrete in macro-and-micro senses,we took the alkali activity of sandstone aggregate of a large hydropower station in China as research background. In consideration of practical engineering demands, we carried out long-age simulation test on fully-graded mass concrete alkali aggregate reaction using SEM (Scanning Electron Microscope) test technology, and in association with the existing assessment system for alkali aggregate reaction, we researched the long-term inhibition of alkali activity. Results suggest that the characteristics of reaction product can be observed evidently by using SEM, the reaction degree can be obtained semi-quantitatively, and the trend of concrete deterioration can be estimated.