Experimental Study On Fiber Bragg Grating Monitoring Of Bolt Deformation Under Complex Stress Conditions

With the popularization and promotion of bolt support technology in China,bolt support has become the most important way of coal mine support.However,since the anchor is a concealed project,in order to ensure the safe use of the bolt,it is of great working significance to understand the reliability of the bolt after the installation and effective monitoring of the bolt.It has played a big role in ensuring the safe production of coal mines.For the monitoring of the tangential load of the anchor,the fiber Bragg grating sensor is selected,and the sensing theory is briefly understood.At the same time,by arranging the fiber Bragg grating sensor on the anchor,the combination of theoretical derivation and experimental verification of the mathematical formula proves that the method is under the condition of monitoring the tangential load of the anchor.Firstly,this paper analyzes the data required to obtain the angle to arrange the fiber Bragg grating sensor.Through the theoretical derivation of the mathematical formula,a set of formulas for the strain value of the anchor is obtained,and the data obtained by the experiment is substituted into the formula.This arrangement enables the angle of the force direction of the anchor to be measured.Then through 7 sets of experiments to analyze the deflection of the bolt when subjected to tangential load,and compare it with the actual measurement,the feasibility and reliability of the fiber Bragg grating sensor as a strain sensor are obtained.The accuracy is better than the ordinary strain.The sensor is more precise.