As corrosion has slow development, its detection at an early age could be an alternative for reducing costs of structural rehabilitation. Therefore, the employment of structural health monitoring (SHM) systems, sensing configurations collecting data over time allowing for observing changes in the properties of the materials and damage emergence, for monitoring corrosion can be a good strategy to measure the damage and to decide the better moment for intervention. Nonetheless, the current corrosion sensor technology and the high costs of the sensing system implementation are limiting this application in the field. In this work, an optical fiber Bragg grating (FBG)-based sensing system is proposed for monitoring the thickness loss of a 1020 carbon steel metal plate subjected to controlled corrosion. The natural frequency of the plate was collected as a function of the corrosion time over 3744 h. To validate the experimental results, ultrasound measures and electrochemical tests were also carried out under similar conditions. The experimental results show adequate reliability, indicating the suitable functionality of the proposed system for monitoring the thickness loss caused by corrosion in metallic structures, in comparison with traditional methods, as ultrasonic and electrochemical measures.

中文翻译：

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基于FBG的金属结构腐蚀监测传感系统

由于腐蚀发展缓慢，因此在早期对其进行检测可能是降低结构修复成本的替代方法。因此，使用结构健康监测 (SHM) 系统、传感配置随着时间的推移收集数据，以便观察材料特性的变化和损坏的出现，监测腐蚀可能是测量损坏和决定更好的策略干预的时刻。尽管如此，目前的腐蚀传感器技术和传感系统实施的高成本限制了该领域的应用。在这项工作中，提出了一种基于光纤布拉格光栅 (FBG) 的传感系统，用于监测受控腐蚀的 1020 碳钢金属板的厚度损失。收集板的固有频率作为超过 3744 小时腐蚀时间的函数。为了验证实验结果，还在类似条件下进行了超声测量和电化学测试。实验结果显示出足够的可靠性，表明与传统方法（如超声波和电化学测量）相比，所提出的系统在监测金属结构腐蚀引起的厚度损失方面具有合适的功能。