早期硬化混凝土中氯离子含量检测方法对比研究

Comparative Study on Detection Methods for Chloride Ion Content in Early Hardening Concrete

对比直接滴定法、电位滴定法、氯离子选择电极法、离子色谱法测试的砂浆中氯离子浓度差异,分析龄期和矿物掺合料种类对氯离子含量的影响规律。结果表明:电位滴定法能满足较宽范围的氯离子浓度测试,精度高、重现性好;混凝土中水溶性氯离子含量随龄期延长而逐渐降低,酸溶性氯离子含量与龄期长短无关;水泥基材料中活性Al_2O_3含量,决定着固化氯离子能力的高低;早龄期(28d)下,矿粉对氯离子的固化能力大于粉煤灰。

The differences of chloride ion concentration in the mortar were compared with the gelard method,potentiometric titration method,chloride ion selective electrode method and ion chromatography method.The influence of age and mineral admixture on chloride ion content was analyzed.The results show that:potentiometric titration method can meet a wide range of chloride ion concentration test,and has high precision and good reproducibility;The water-soluble chloride ion content in concrete gradually decreases as the age increases,and the acid solubility Chloride ion content has nothing to do with the length of age;The content of active Al2O3 in cement-based materials determines the ability of solidifying chloride ions;under the early age(28 d),the solidification ability of chloride powder for chloride ions is greater than fly ash.