| 摘要: |
| 采用干湿循环的方式来加速钢筋锈蚀，同时运用声发射（AE）技术对钢筋锈蚀过程进行监测，研究了水泥基材料中钢筋锈蚀过程的声发射信号特征.结果表明：砂浆在养护过程中伴随有大量的声发射信号，其峰值频率主要集中在20~60kHz和130~200kHz；水泥基材料在吸水湿胀和脱水盐析过程中均伴随有声发射信号，其声发射信号峰值频率约为50kHz；基于声发射信号能量分布统计分析和b值法，能够较为准确地确定水泥基材料中钢筋锈蚀的产生情况；钢筋钝化膜破裂的声发射信号峰值频率位于100~150kHz，钢筋点蚀的声发射信号峰值频率位于20~70kHz. |
| 关键词: 声发射 锈蚀 钢筋 混凝土 |
| DOI：103969/j.issn.1007 9629201903009 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51379111） |
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| Characteristics of Acoustic Emission Signals from Initial Corrosion of Steel Bar in Cement Based Materials |
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XU Gang, ZENG Zhen, ZHANG Rui, PENG Yanzhou, YANG Zewen
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Hubei Key Laboratory of Disaster Prevention and Mitigation, China Three Gorges University, Yichang 443002, China
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| Abstract: |
| Acoustic emission（AE）technology was used to monitor the corrosion process of steel bars by using the accelerated corrosion method of dry and wet cycles. The aim of test was to study AE signal characteristics of steel bars in the process of corrosion in cement based materials. The results show that the mortar is accompanied by a large number of AE signals during the curing process,and the peak frequency is mainly concentrated in two frequency bands of 2060kHz and 130200kHz.The cement based materials are accompanied by AE signals in the process of water absorption and dehydration, and the peak frequency of AE signals is about 50kHz. By using the statistical analysis of AE signal energy distribution and b value method, it can accurately determine the occurrence of steel bar corrosion in cement based materials.The peak frequency range of AE signal corresponding to the rupture of passivation film of steel bars is 100150kHz, while that to pitting is concentrated at 2070kHz. |
| Key words: acoustic emission（AE） corrosion steel bar concrete |
