Research Of Engineering Properties Of Bolts In Coal Mining Roadway With Shallow Depth And Thin Bedrock

Bolt support is a kind of active control technology,which is widely used in coal mine roadway.The field monitoring of bolt supporting quality is very important to the stability analysis and parameter optimization of support.In order to achieve the long-terltm dynamics of roadway surrounding rock continuous monitoring,the possible disaster timely warning.According to the Ordos coal field of shallow buried depth,thin bedrock,the research focus on mining influence on roadway stability and other characteristics in shallow thin bedrock coal roadway bolting support technology and application.In Daliuta coal mine 52302 working face as research object,based on shallow buried thin bedrock coal seam geological conditions and mining conditions,the roadway supporting structure of the full size three-dimensional mechanical calculation model was established,the roadway bolt supporting parameters was designed.According to the method of numerical simulation,the distribution and variation law of bolt at different position of mining roadway under mining action are determined.The fiber Bragg grating anchor stress sensor has been developed,which is applied to the monitoring system of the optical fiber grating for the support of the surrounding rock.Integrated field monitoring fiber Bragg grating sensor,underground optical fiber communication ring network,fiber optic grating modulation and demodulation instrument data acquisition,data acquisition and optical fiber transmission technology.The real time monitoring and data analysis in the monitoring process was completed.Based on Fiber Bragg grating sensor technology,continuous dynamic monitoring of deformation of surrounding rock,internal force and deformation of support structure is realized.Application of fiber Bragg grating anchor stress monitoring system in the 52302 working face,the stress change of anchor support structure is monitored in real time.The stress evolution characteristics of the anchor rod in the working face advancing process are revealed.The theoretical basis for the design of anchor support parameters and the optimization of the structure of the anchor rod is provided in the similar condition.