基于光纤光栅技术的围岩大应变连续监测研究  

Research on continuous monitoring of large strain in surrounding rock based on fiber grating technology

作　　者：李秀文[1] 朱赵辉[1] 王万顺[1] 孙建会[1] LI Xiuwen;ZHU Zhaohui;WANG Wanshun;SUN Jianhui(China Institute of Water Resources and Hydropower Research,Beijing IWHR Co.,Ltd.,Beijing,100038,China)

机构地区：[1]中国水利水电科学研究院北京中水科工程总公司

出　　处：《中国水利水电科学研究院学报》2019年第3期197-203,共7页Journal of China Institute of Water Resources and Hydropower Research

基　　金：国家重点研发计划项目(2017YFC1501201);国家自然科学基金项目(51409284)

摘　　要：围岩应变是地下洞室开挖监测的重要内容之一,采用传统应变监测仪器无法测得连续的围岩大应变。本文结合工程实践,基于光纤光栅位移传感器设计出一种连续测量围岩大应变的改进型大量程光纤光栅应变监测装置。该装置将多支改进型大量程光纤光栅应变传感器组装成串,可连续测得仪器埋设沿线任一测点的应变量。监测成果表明,洞室扩挖时光纤光栅仪器测得围岩应变变化明显,与埋设部位围岩地质结构和施工开挖实际较为吻合,与附近多点变位计监测结果变化规律基本一致。由于光纤光栅仪器具有灵敏度高、精度高等优点,因此能够监测到安装孔内轴向任意间距围岩应变情况。The surrounding rock strain is an important content inmonitoring the underground cavern excava tion,but the large strain of surrounding rock cannot bemonitored by the traditional strainmonitoring instru ments.Combining with engineering practice and based on fiber Bragg grating displacement sensor, an im proved wide range fiber Bragg grating strainmonitoring device that can continuouslymonitor large strain of surrounding rock was designed. The improved device assembles severalmodified wide range fiber Bragg grat ing strain sensors to continuouslymonitor the strain value at any point along the buried devices. The results show that the fiber Bragg gratingmonitored obvious strain variations of surrounding rock when expanding the excavation of the caverns. The variations were identical to the surrounding rock geological structure and the practical construction excavation and were basically consistent with the variations that weremonitored by near bymulti-point extensometer. Because the improved instrument has the advantages of high sensitivity and high precision,it canmonitor the strain variation of the surrounding rock at any spacing on the axial direc tion of the installation hole.

关 键 词：光纤光栅技术 地下洞室 围岩应变 监测 

分 类 号：TV64[水利工程—水利水电工程]