The Experiment Study Of Anchor Inspection On Optical Fiber Sensor

Technology of anchor bolt shaft has become a key technology projects in slope, mine, and the stability of tunnels, especially in the coal mine under the effect of continuous mining, Anchor stay in a special working conditions, and its stress state is very complex, anchorage system makes the security of the stress state becomes very difficult to monitor. Fiber grating sensing technology has its own unique properties and wide application prospect, with the detection of Bolt Anchorage, exploring for detection of fiber grating bolts for anchoring mechanism to raise awareness of and understanding of deformation mechanism has very important practical significance.In this thesis, we start from the anchoring mechanism to the fiber grating sensor characteristics and the role of anchoring engineering principles as the theoretical basis for analysis the feasibility of fiber grating anchor bolt system in quality inspection. The fiber grating detection experiments had designed to verify the change in grating wavelength range of parameters and bolt bearing capacity of the bond between mild, indicating that the fiber grating has a good test performance.Uses a new sensor, which is based on the ends of fiber grating sensor bolt force, mainly composed of the sensor in the ring with homogeneous elastic wall over fiber grating, while the bolt shaft sensor layout, and finally multiple FBG series with a conductive fiber in the same wavelength of the signal came through it, the fiber grating demodulator FBG wavelength detection value△λ, obtained by theoretical calculation bolt axial force F and the amount of FBG wavelength shift between△λrelationship. According to the mechanical behavior of fiber grating, for a similar performance simulation and related experiments, the amount of fiber grating wavelength shift with the variation of the load.From the experimental analysis, in two different proportions in different anchoring system that bond strength bolt under the fiber grating wavelength amplitude significantly increasing trend. Drawing experiment tests that the accuracy of FBG and conventional strain gauge precision quite. The monitoring system can be used to monitor the mine bolt for the realization of the security status of roadway maintenance and safety to provide the scientific protection. The technology for improving the quality of bolt monitoring and monitoring of the reliability of evaluation results is important.