为快速、准确地测定混凝土中氯离子的含量,以实现对混凝土耐久性的有效评价和钢筋腐蚀的适时防护与有效修复,研究现场测试氯离子渗透性的方法是非常必要的.结合客运专线工程施工情况,分别按矿物掺合料不同掺量以及不同的强度等级进行配合比设计试验,采用PERMIT离子迁移仪对混凝土试件进行氯离子扩散系数的测定,并采用电通量法进行验证.结果表明:随着电通量的增加,氯离子扩散系数呈现增加的趋势,二者存在很好的线性关系;双掺粉煤灰+矿粉的混凝土抗氯离子侵入性优于单掺粉煤灰的混凝土;PERMIT离子渗透试验方法测得的试验结果准确可靠,具有很强的实用性.可以为混凝土耐久性的判定提供依据.%For rapid and accurate determination of chloride content in concrete to achieve the effective evaluation of the durability of concrete and steel corrosion protection and effective timely repair. The study of chloride ion permeability field test method is very necessary. Combining with the construction works of a passenger railway line, mix ratio tests were designed respectively for concrete with different contents of mineral admixtures and different strength grades. PERMIT ion mobility instrument was used to determine the chloride ion diffusion coefficient of concrete specimens. The results show that, with the increase of electric flux, chloride ion diffusion coefficient showed an increasing trend, both with good linear relationship. Fly ash and slag concrete resistance to ingress of chloride ions was better than concrete singly added with fly ash. The measured test results of PERMIT ion penetration test method are accurate and reliable, and highly practical. It can provide basis for determining the durability of concrete.
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