海洋环境下锈蚀混凝土的新型电化学除氯工艺参数研究

Process Parameter Study on New Electrochemical Chloride Extraction of Corroded Concrete in Marine Environment

电化学除氯(ECE)是一种针对锈蚀混凝土的无损处理技术,可以降低钢筋的腐蚀风险,提高混凝土耐久性,但对电化学除氯关键参数缺乏深入研究。为进一步探索电化学除氯技术的关键参数,以不锈钢网为阳极材料,研究了电解液、电流密度和钢筋类型对电化学除氯效率的影响。分别对含有耐蚀钢筋和普通碳素钢筋的混凝土进行了电化学除氯处理,以研究不同种类钢筋对混凝土的除氯作用。采用扫描电子显微镜(SEM)分析了电化学除氯前后混凝土的微观形貌演变。试验结果表明:电化学除氯效率随电流密度的增加而提高,综合考虑后确定最佳的电流密度为2 A/m^(2)。Ca(OH)_(2)溶液作为电解质溶液时,除氯效率最高。同时,试验发现钢筋类型对混凝土的除氯效率没有明显的影响。

Electrochemical chloride extraction(ECE)is a kind of non-destructive treatment technology for corroded concrete,which can decrease the corrosion risk of reinforced concrete and improve the durability of concrete.However,the key parameters of ECE need be studied more.In order to explore the key parameters of ECE,the effects of electrolyte solution,current density and steel bar type on the efficiency of ECE treatment were studied by using stainless steel mesh as anode material.Electrochemical chloride extraction of concrete containing corrosion-resistant steel and ordinary carbon steel was used to investigate the dechlorination effect of different kinds of steel on concrete.Moreover,scanning electron microscopy(SEM)was applied to analyze the micromophrlogy evolution of concrete before and after ECE.Experimental results showed that the ECE efficiency increased with the increase of current density,and the optimal current density was 2 A/m^(2) after overall consideration.When electrolyte solution was Ca(OH)_(2) solution,the efficiency of ECE was the maximum.In addition,the reinforced steel type had no obvious effect on the ECE efficiency of concrete.