有压溶液作用下混凝土中氯离子浓度分布研究

Experimental research on distribution of chloride in concrete under stressed chloride solution

为探索测定混凝土中钢筋锈蚀临界氯离子浓度的快速测定方法,本文对有压溶液作用下混凝土内部的氯离子浓度分布进行了测定。试验测定了0.65水灰比、1 MPa压强作用下混凝土的渗透系数以及不同加压时间条件下的自由氯离子浓度和总氯离子浓度,得到了不同加压时间下自由氯离子沿混凝土深度的浓度分布曲线。结果表明,随着加压时间的增长,在同一混凝土渗透深度处,自由氯离子浓度呈上升趋势。数值模拟的结果也较好的反映了这一规律。这为钢筋锈蚀临界氯离子浓度的快速测定方法的提出提供了理论及实验基础。

In order to explore a quick experimental method measuring the chloride threshold level in concrete,an experimental research on the distribution of chloride concentration in concrete under stressed solution is introduced. The permeability coefficient of concrete with 0. 65 w/e under 1.0 MPa pressure and the chloride concentration for different pressuring time are measured. The distributions of the chloride eoneentration along the depth of concrete are obtained. The results show that, with pressing time increasing, the free chloride concentration increases at the same depth in concrete. The conclusions from numerical simulation agree well with experimental results. The present paper provides good experimental and theoretical bases for the quick method measuring the chloride threshold leVel in concTete.