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实验室常用外加电压来加速氯离子在水泥基材料中的迁移,缩短试验时间。本文对外加电压下不同因素对氯离子迁移特性的影响、外加电压对氯离子结合和解吸附、水泥基材料孔结构及水化产物的影响进行了综述。外加电压的变化对非稳态电迁移系数影响不明显,氯离子浓度对稳态迁移系数有影响,使用矿物掺合料时不同试验得到的迁移系数间的差异变小,硅灰作用最明显,其次是粉煤灰。不同试验条件时电压对氯离子的结合的影响也不同。反加电压会促使结合氯离子的解吸附及200 nm以下孔结构的细化,同时对水化硅酸钙(C–S–H)的分解及Friedel’s盐形成也有一定的影响。
Laboratory commonly used voltage to accelerate the migration of chloride ions in cement-based materials to shorten the test time. In this paper, the effects of different factors on the migration of chloride ions under the applied voltage were studied. The effects of applied voltage on the chloride ion desorption, the pore structure of cement-based materials and the hydration products were reviewed. The change of applied voltage has no obvious effect on the non-steady state electromigration coefficient, and the chloride ion concentration has an influence on the steady state migration coefficient. When the mineral admixture is used, the difference between the migration coefficients obtained by different experiments becomes smaller, Followed by fly ash. The effect of voltage on the combination of chloride ions is also different for different test conditions. The reverse voltage increases the desorption of the bound chloride ion and the refinement of the pore structure below 200 nm, as well as the decomposition of hydrated calcium silicate (C-S-H) and Friedel’s salt formation.