| 摘要: |
| 为分析氯盐环境下粉煤灰对混凝土中钢筋锈蚀过程的影响,设计制作了粉煤灰掺量为0%、10%和20%的水泥净浆钢筋试件,并在质量分数为35% NaCl溶液中进行了钢筋腐蚀过程的电化学测试和水泥浆体的微观测试,获得了不同浸泡时间条件下的Tafel极化曲线、电化学阻抗谱(EIS)曲线、水泥浆体的物相组成和钢筋表面脱钝氯离子阈值,分析了粉煤灰掺量对试件中钢筋腐蚀过程和水泥浆体物相组成的影响.结果表明：用粉煤灰部分替代水泥可以增加混凝土中钢筋的脱钝锈蚀时间,提高水泥浆体中C S H凝胶和Friedels盐的含量,但会降低钢筋表面脱钝氯离子阈值.因此,在混凝土中掺入适量粉煤灰可以提高水泥浆体对氯离子的固化能力,延缓混凝土中氯离子的传输进程,改善氯盐环境下混凝土结构的耐久性能. |
| 关键词: 钢筋混凝土 粉煤灰 氯盐环境 电化学 物相 氯离子阈值 |
| DOI：103969/j.issn.1007 9629202004020 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(51778297,51378262) |
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| Corrosion Process of Steel Bar in Fly Ash Concrete under Chloride Environment |
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ZUO Xiaobao, ZOU Shuai, LI Xiangnan, ZHENG Zhikang
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Department of Civil Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
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| Abstract: |
| In order to investigate the influence of fly ash on the corrosion process of steel bar in concrete under chloride environment, a series of cement paste steel bar specimens with 0%, 10% and 20% fly ash had been prepared to perform their corrosion experiment in 35% NaCl solution. By using electrochemical and microscopic measurements, Tafel and EIS curves in different soaking time were observed, and the phase composition of paste and the depassivated chloride threshold of steel related to fly ash content were obtained. |
| Key words: reinforced concrete fly ash chloride environment electrochemistry phase composition chloride threshold |
