边坡工程分布式光纤监测技术研究

 通过对边坡及其加固工程进行实时、在线监测，可掌握边坡的变形动态，对滑坡进行预警。分布式光纤传感技术与常规监测方法相比具有很大的优越性，如分布式、长距离、实时性和长期稳定性等，可满足加固工程安全监测和滑坡早期预警的要求。对布里渊光时域反射技术(BOTDR)的测量原理和优点进行介绍，设计一套基于BOTDR的新型分布式边坡监测系统，详细阐述工程应用中传感光纤的布设方法、光纤保护和温度补偿技术等。通过将传感光纤按一定的方式布设在加固工程及坡体内，并相互连接构成基于BOTDR的边坡分布式光纤监测系统，进而实现对整个边坡的远程分布式监测。以实际工程为例，对边坡分布式变形监测结果进行分析。结果表明，基于BOTDR技术的边坡分布式光纤监测系统能够准确地反映边坡及加固工程的变形情况，具有显著的优越性，可用于边坡稳定性的监测和预报。

STUDY ON DISTRIBUTED OPTICAL FIBER SENSOR-BASED MONITORING FOR SLOPE ENGINEERING

Real-time and on-line monitoring of slope and reinforcement works are useful for mastering the deformation dynamics and early warning of the landslide in time. In comparison with the conventional monitoring methods，distributed fiber optic sensing offers a number of advantages including distributed monitoring，long distance，real-time monitoring，long-term stability，et al. so as to meet the demand of early warning of landslide and health monitoring of slope engineering. The measurement principles and merits of Brillouin optical time-domain reflectometer(BOTDR) are introduced. And a novel distributed fiber optic sensor-based monitoring system for slope engineering is expounded. The relative topics about application of BOTDR in slope engineering are discussed including installation methods of optical fiber，optical fiber protection and temperature compensation method. To realize the remote distributed monitoring of the slope and reinforcement works，fiber optic sensors，which are connected with each other to form a BOTDR-based remote distributed monitoring system，are installed in the reinforcement works and the slope in some ways. Then taking a project as example，the deformation monitoring data are analyzed. And the monitoring results show that，in slope engineering，the state of deformation can be exactly reflected by BOTDR-based distributed monitoring system，which has obvious advantages in terms of slope deformation monitoring and real-time landslide prediction.