Chloride Ingress into Alkali-Activated Concrete Under Drying-Wetting Cycles

被引：0

作者：

Bao J. ^{[1
]}

Zhang X. ^{[1
]}

Zhang P. ^{[1
]}

Cui Y. ^{[1
]}

Wei J. ^{[1
]}

Zhuang Z. ^{[1
]}

机构：

[1] Department of Civil Engineering, Qingdao University of Technology, Qingdao

来源：

Kuei Suan Jen Hsueh Pao/Journal of the Chinese Ceramic Society | 2022年 / 50卷 / 06期

关键词：

Alkali-activated concrete; Chloride ingress; Drying-wetting cycles; Marine environment; Numerical model;

D O I：

10.14062/j.issn.0454-5648.20210839

中图分类号：

学科分类号：

摘要：

Alkali-activated concrete (AAC) prepared without cement with the performance of rapid hardening, high strength and good durability, is recognized as one of novel green building materials with a wide application potential. Chloride ingress into concrete to cause the process of steel corrosion is one of the main reasons to the durability failure of reinforced concrete structures, particularly exposed to marine cyclic drying-wetting zones. It is thus of great significance for the development of durability theory to conduct the chloride ingress resistance analysis of AAC under drying-wetting cycles. Compared with concrete C50, the effects of cyclic drying-wetting time ratio (i.e. 3.0:1.0, 11.0:1.0 and 85.4:1.0) and exposure time (i.e. 30, 90 and 180d) on the chloride ingress properties of AAC were investigated via a designed automatic experimental set-up of cyclic drying-wetting test. A theoretical model of chloride ingress into AAC under drying- wetting cycles was proposed for numerical calculation. The results show that the chloride content within AAC is obviously less than that in concrete C50. This is because AAC has a smaller porosity and a denser pore microstructure rather than concrete C50, thus exhibiting a better resistance to chloride ingress. The surface chloride concentration and apparent chloride diffusion coefficient of AAC first increase and then decrease as the cyclic drying-wetting time ratio increases. It is indicated that the numerical data of chloride profiles calculated by the proposed model of chloride transport into unsaturated concrete under various conditions of the drying-wetting cycles are in reasonable agreement with the experimental results. © 2022, Editorial Department of Journal of the Chinese Ceramic Society. All right reserved.

引用

页码：1607 / 1615

页数：8

共 23 条

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