Experimental Study on the Evaluation of Chloride Ion Penetration in Cracked Concrete by the Method for Effective Diffusion Coefficient

本研究探讨了氯离子侵蚀检测中钢筋处氯离子浓度扩散系数的估算方程（JSCE方程）。为了评估氯离子在不同类型裂缝的钢筋混凝土结构上的渗透性，采用混凝土保护层模型试件进行了电迁移试验。在此基础上，建立了氯离子扩散系数的评价方程（建议方程）。在建议的公式中，应用范围的限制已扩大到包括各种裂缝条件和各种钢筋混凝土构件。对于JSCE公式的极限扩展，本研究采用裂缝面积比（裂缝面积与混凝土面积的比值）和代表裂缝影响的常数随裂缝深度的减小来表示所提出的公式。

This study was investigated the Evaluation Equation (JSCE Equation) of diffusion coefficient for chloride concentration at the location of reinforcement which is used in the examination of chloride attack. The electrical migration tests were carried out using specimens modelized concrete cover with various types of cracks in order to evaluate chloride ion penetration on reinforced concrete structures with diversified types of cracks. In the results, this study was built to evaluate equation (proposed equation) of diffusion coefficient of chloride ion. In the proposed equation, the limit on the range of application has been expanded to include various crack conditions and various reinforced concrete members. For the expansion of limit of JSCE Equation, this study was used the crack area ratio (the ratio of crack area to concrete area) and the decreasing of the constant which represents the effect of cracks according to the depth of cracks for the proposed equation.