混凝土电化学除氯过程钢筋周围氯离子迁移规律试验研究

Experimental research on chloride migration regularity around steel-bar during electrochemical chloride extraction for reinforced concrete

随着服役年限增长,氯盐环境中钢筋混凝土结构的耐久性劣化问题越来越突出。电化学除氯技术是钢筋混凝土耐久性修复重要方法,可有效排除保护层中氯离子,然而电化学除氯过程混凝土内部氯离子迁出规律有待研究。重点研究了电化学除氯过程中钢筋周围氯离子迁出的空间规律。结果表明,电化学除氯结束后,钢筋周围氯离子浓度降低显著,保护层内随着距离钢筋径向距离的增加,残余氯离子浓度增大,表现出明显的非均匀分布。研究成果可为进一步完善钢筋混凝土电化学除氯后的耐久性评估和寿命预测提供依据。

With the increase of service life, the durability deterioration of reinforced concrete structures in chloride environment has be- come increasingly outstanding.The electrochemical chloride extraction technology is an essential method for RC durability restoration, which can remove the chloride in concrete cover effectively.However, Me regularity of chloride migrating outside of the concrete during the electrochemical chloride extraction should be studied further.This paper studied on the spatial characteristics of the chloride migra- tion during the electrochemical chloride extraction.The results showed that after electrochemical chloride extraction, the chloride concen- tration decreased significantly. Moreover, with the growth of radial distance from the reinforcement, the concentration of residual chloride became higher, which represented the non-uniform distribution of chloride obviously. This research results can provide further reference for durability evaluation and life prediction after electrochemical chloride extraction.