Field Test of Hydraulic Fracturing and Weakening of Hard Roof to Protect Gob-side Roadway

For the problems of large deformation and strong underground behavior of gob-side roadway in Majiliang Coal Mine, the field experiment of hydraulic fracturing in hard roof was proposed. Through the comparison of monitoring borehole and stress variation of borehole stress meter, the efficiency of hydraulic fracturing in hard roof was analyzed. The results show that the hydraulic fracturing could effectively weaken the hard roof and reduce the stress concentration of the working face. The research results provide a foundation for the promotion application of hydraulic fracturing technology, and the effect is remarkable for controlling underground behavior of gob-side roadway. The successful implementation not only realizes the normal mining of 8103 working face, but also provides a measure for reducing stress concentration of gob-side roadway.