Abstract:

The purpose of the paper is to develop a kind of highfrequency realtime monitoring technology so as to insight into the deformation of the ground ahead of the tunnel face. Model design, indoor experiment and application verification are made on basis of the study results of distributed optical fiber monitoring technology. In the end, a kind of technology that can monitor the deformation of ground ahead of the face of soil tunnels is developed, the mechanical model of the monitoring and the monitoring equation are achieved, and the technology of the fabrication and calibration of the optial fiber sensors, the layout and installation of the sensors, and the system integration and realtime monitoring are proposed. The study results have been applied in actual works and good effects have been achived. 

Key words: BOTDR, Shijiazhuang tunnel, sandy clay, displacement monitoring