中文摘要：

混凝土是一种多相复合材料，其中砂浆、骨料、界面过渡区（ITZ）都对氯离子传输有着重要影响。分别通过电子探针线扫描和面扫描技术，对ITZ宽度进行了测量，并获得混凝土断面氯离子精确浓度分布。基于并联传输模型，通过试验测得ITZ中氯离子扩散系数。建立数值模型对氯离子传输过程进行了模拟，并通过与电子探针面扫描结果对比，验证了模型的可靠性。结果表明，将混凝土考虑成三相复合结构，数值模型更接近氯离子的真实传输过程。

英文摘要：

Concrete is a multiphase composite material,in which the mortar, aggregate and interracial transition zone （ ITZ ） have important influence on the chloride ion transport.The ITZ width was measured and the exact concentration distribution of chloride ion in concrete section was obtained through electron probe analysis.Based on the parallel transmission model, the diffusion coefficient of chloride ion in ITZ was determined from experiment.Based on the measured ITZ parameters, a numerical model was established to simulate the chloride ion transfer process and the reliability of the model was verified by comparing the numerical simulation with the surface scanning results collected from the electron probe.The test results show that if the concrete is taken as a three-phase composites, the numerical model can reflect the real transmission process of chloride ion more accurately.