基于光纤传感技术的隧道结构安全监测系统研究

Research on Tunnel Structure Safety Monitoring System Based on Fiber Optic Sensing Technology and Image Matching Technology

为了动态获取、处理和反馈隧道安全运营情况,基于光纤传感技术和图像匹配技术原理,设计了一种隧道结构安全监测系统。该系统由FBG应变传感器和视频位移计组成,可实现隧道衬砌结构应变、位移的实时远程采集和在线监测,目前该系统已在甘肃陇南两水隧道中应用。研究表明,该系统应变监测精度可达到με级;位移精度可达亚mm级;应变和位移变化在过车后具有较好的归零特性。最后,结合视频位移计和FBG应变传感器在同一点位的数据进行监测,结果表明,该视频位移计与FBG应变传感器波动基本一致,可满足隧道运行期的安全监测要求。

In order to obtain,process and feedback the tunnel safety operation situation dynamically and timely,a tunnel structure safety monitoring system was designed based on the principle of optical fiber sensing technology and photogrammetric technology.The system consists of fiber grating strain sensor and video displacement meter.It can realize real-time remote acquisition and on-line monitoring of both strain and displacement of tunnel lining structure.At present,the system has been applied at Liangshui tunnel in Longnan,Gansu Province.The results show that the strain monitoring precision of the system can reach~μεby comparison of the measurement results tunnel before after and long-term operation stability.Displacement accuracy up to sub millimeter;Finally,combined with the data of the video displacement meter and the Fiber Bragg Grating strain sensor at the same point,the analysis results show that the fluctuation of the video displacement meter and the Fiber Bragg Grating sensor are basically consistent,which meets the safety monitoring standard during tunnel operation.