养护龄期和矿物掺合料对砂浆氯离子结合能力的影响

Effect of curing age and mineral admixture on chloride ion binding capacity of mortar

为研究养护龄期和矿物掺合料对砂浆氯离子结合能力的影响规律,通过比较不同氯离子浓度检测方法的准确度和重现性,确定自动电位滴定法为最佳检测方法。采用自动电位滴定法,对不同养护龄期和掺入不同矿物掺合料的砂浆试样进行水溶性氯离子和酸溶性氯离子研究。结果表明,砂浆中水溶性氯离子含量随龄期延长而逐渐降低,而酸溶性氯离子含量与龄期无关;矿物掺合料中活性SiO_2和活性Al_2O_3含量,决定着固化氯离子能力;在中长龄期(180d)下,粉煤灰对氯离子的固化能力要大于矿粉的。

In order to study the influence of curing age and mineral admixture on the chloride ion binding ability of mortar,we compare the accuracy and reproducibility of different chloride ion concentration detection methods,determine the automatic potentiometric titration method as the best detection method,and research water-soluble chloride ions and acid-soluble chloride ions by automatic potentiometric titration for mortar samples of different curing ages and different mineral admixtures.The results show that the content of water-soluble chloride ions in mortar decreases with age,while the content of acid-soluble chloride ions has nothing to do with the length of age.The content of active SiO2 and active Al2O3 in mineral admixture determines the ability to solidify chloride ions.In the middle and long age (180d),the solidification ability of fly ash to chloride ion is greater than that of mineral powder.