Abstract: Cracking of secondary lining structure is a major disease affecting the health of tunnel. As the traditional monitoring instrument is constrained to the long distance and other characteristics of diversion tunnel, this paper introduces an embedded FBG strain sensor applied. The layout program is put forward and the safety monitoring system is established by sensors and demodulators. After long-term monitoring, data processing and analysis, the result shows that data curves are consistent with the actual stress. Further, the feasibility and advantage of application of FBG sensor in safety monitoring of the secondary lining of diversion tunnel are proved.

Key words: FBG, strain sensor, diversion tunnel, secondary lining, monitoring

摘要： 二次衬砌结构裂化是影响隧道健康的主要病害，传统监测仪器受限于引水隧道的长距离等特点，现引入一种埋入式FBG应变传感器，并应用于某引水隧道，提出了具体的布设方案，通过传感器、解调仪等构建了安全监测系统。应变监测成果与类似工程基本一致，表明了FBG传感器在引水隧道二次衬砌结构安全监测过程中的可行性以及优越性。

关键词: FBG, 应变传感器, 引水隧道, 二次衬砌, 监测