焦耳热和电极反应对混凝土电通量试验的影响

研究了电通量试验过程中通过被测混凝土试件的电流（，）随测试时间（t）的变化规律及其影响因素。结果表明：当混凝土抗渗性较好时I-t关系曲线起伏变化很小，基本上呈一条直线，而当混凝土抗渗性较差时，由于焦耳热效应和电极反应影响较大，导致在整个测试过程中I-t关系曲线起伏变化剧烈并最终影响混凝土电通量测试结果的准确性。根据I-t关系给出了试验测试过程中是否需要冷水浴的条件；建议采用试验开始时刻通过被测混凝土试件的初始电流值I0来计算混凝土的6h电通量，并给出了计算公式。

Influences of Joule Heating and Electrode Reaction on Rapid Chloride Permeability Testing of Concrete

Rapid choloride migration test（RCMT） is one of the most important measures to evaluate the impermeability of concrete. The variation and influencing factors of electric current through concrete with the testing time was researched by testing different specimens of concrete. It is found that when the permeability of concrete is lower, the current - time curve remained stable, basically in a straight line. In contrast, the electric current increased significantly during the testing proccess when the permeability of concrete is higher. Further studies show that it is primarily caused by Joule heating and electrode reaction. Accordingly, the conditions whether to use water bath is presented. The results support an equation to calculate the coulomb values through concrete by initial current.