钢结构的锈蚀监测对于钢结构安全的早期预警非常重要.本文提出了一种制备布喇格光纤光栅锈蚀传感器的方法，并研究了该传感器在不同湿度环境下的传感规律.结合磁控溅射和电镀的方法在光栅侧表面制备了Fe-C合金传感膜；利用扫描电子显微镜观察其侧表面形貌；检测在相对湿度60%和99%下中心波长的变化，进而分析该光纤光栅探头在不同湿度下的传感规律.实验和数据分析结果表明：在相对湿度为60%时，锈蚀进程缓慢，随着时间的推移波长呈线性化增加；相对湿度达到99%时光栅光谱出现多峰现象.据此得出：一定湿度条件下，该传感器可监测锈蚀进展；当环境湿度较高（达到99%）时，该传感器可用于锈蚀出现的早期预警.

A prototype Fiber Bragg Gratings (FBG) sensor for monitoring corrosion of steel structures was presented and the performances were characterized at different humidities. The sensor was fabricated by sputtering and electroplating a sensitive metal film on FBG side-face. The surface micro-structures of sensor at different humidities were investigated by Scanning Electron Microscope during a 27-day experimental cycle. The shifting of wavelength was recorded by Optical Spectrometer Analyzer in two environments with humidity of 60% and 99% RH. The wavelength of FBG sensor at 60%RH increased linearly with an increment of 0.025 nm per day. For sensors at 99%RH, the chirping appears, which implies more serious corrosion occurs than that at 60% RH. The experimental results show that the proposed FBG corrosion sensor is applicable for corrosion monitoring at a humidity of lower than 60%RH, and applicable for early alert of corrosion at a higher humidity.