钢筋脱钝氯离子阈值快速测定新方法

为了缩短钢筋脱钝氯离子阈值试验测试周期,基于混凝土中氯离子在电场加速作用下快速迁移的特性,提出一种钢筋脱钝氯离子阈值快速测定方法.该测试方法主要存在两大技术问题：外加电场电压确定和钢筋脱钝时刻的判别.为了证明该试验方法的可行性,设计了自然渗透实验进行对比.实验结果表明：电场加速实验能有效区分不同掺合料对氯离子阈值的影响.研究发现,由自然渗透实验测得的氯离子阈值略大于电场加速实验得到的氯离子阈值,两者比值为1.1～1.3,从而验证了该加速实验方法的可行性.

New fast test method to determine chloride depassivation threshold of rebar in concrete

A fast test method to measure the chloride threshold by adding accelerated field was put forward to shorten the test cycle. Two technical problems of this test method were discussed: one is voltage determination of external electric field, and the other is distinguishing depassivation of the rebar in concrete. In order to verify the feasibility of this method, two comparative experiments were designed: natural penetration experiment, and chloride penetrating experiment by adding accelerated field. The results show that this quick experimental method can distinguish the influence of additional materials on chloride threshold. Furthermore, the chloride threshold value measured by the natural penetration experiment is a little bigger than the value measured by this quick method, and the ratio of them is about 1.1～1.3, which proved the feasibility of this fast test method．