Ionic transport in cementitious materials under an externally applied electric field: Finite element modeling
Ionic transport in cementitious materials under an externally applied electric field: Finite element modeling
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DOI：
10.1016/j.conbuildmat.2011.07.019
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发表时间：
2011-08
影响因子：
7.4
通讯作者：
Yajun Liu;Xianming Shi
中科院分区：
文献类型：
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作者：
Yajun Liu;Xianming Shi
钢筋锈蚀是钢筋混凝土和其他胶凝材料的主要劣化机制，通常是由于除冰剂或海洋环境中的氯离子进入造成的。电化学氯化物萃取技术是一种在世界范围内得到广泛应用的有效缓蚀技术。在这项工作中，利用外加电场的加速迁移试验来研究氯离子在胶凝材料中的迁移，其结果被逆参数化为氯离子扩散系数。然后，对离子物质在水泥浆、砂浆和混凝土材料中的迁移进行了计算研究。用有限元方法建立了描述不同物种时空演化的非线性偏微分方程组，讨论了不同物种之间的离子相互作用、氯离子结合、聚集体和裂纹的作用等非均质材料的重要影响因素。
Rebar corrosion is a major deterioration mechanism for reinforced concrete and other cementitious materials, which is often resulted from the ingress of chloride ions from deicer applications or marine environments. Electrochemical chloride extraction (ECE) is an effective corrosion mitigation technique that is gaining world-wide application. In this work, accelerated migration tests with the aid of an externally-applied electric field were utilized to investigate chloride transport in cementitious materials, the results of which were inversely parameterized to extract chloride diffusion coefficients. Computational studies on transport of ionic species during ECE in cementitious paste, mortar, and concrete materials were then explored. The nonlinear partial differential equations to characterize spatial and temporal evolution of various species were formulated with the finite element method (FEM), and important factors for heterogeneous materials, such as ionic interactions between various species, chloride binding, role of aggregates and cracks, were discussed.