Abstract: The fiber Bragg grating displacement sensor which based on cantilever structure connected by force conduct rod forms fiber Bragg displacement sensor link string by connecting head and end. It dismisses impact on the adjacent displacement meters by the springs installed under the flange. And it's worthy noting that the impact on the displacement meters from temperature is dismissed by the grating attached on the up and down side of the sensitive area of the cantilever, and we get the corresponding relation between grating's wave length and displacement. After the onsite comparison test, we found this displacement sensor can realize the aim of installing multiple instruments in the small hole at the same time.

Key words: fiber Bragg grating, displacement of surrounding rock, distributed sensing

摘要： 基于不锈钢测杆连接悬臂梁结构的光纤布拉格光栅位移传感器，通过首尾连接形成光纤布拉格位移传感链路串。本设计利用安装在法兰盘下方的弹簧消除相邻各位移计的影响，同时在悬臂梁敏感位置上下两侧粘贴光栅消除温度对位移的影响，得到光栅波长与各段传感器实际位移的对应关系。通过现场对比测试，可实现在小口径的测量孔中安装位移传感链路串，提高围岩位移监测分辨率。

关键词: 光纤布拉格光栅, 围岩位移, 分布式传感