Experiment Study on Mine Pressure Bumping Prevention and Control with Directional Hydraulic Fracturing in Seam

The seam pressure releasing with the directional hydraulic fracturing could prevent and control the mine pressure bumping occurred.Meanwhile the KBD 5 electromagnetic radiation monitoring and measuring instrument was applied to monitor and measure the experiment results.The results showed that after the direction al hydraulic fracturing conducted, the electromagnetic radiation value within 1020 m around the fractured borehole was significantly reduced than before the fracturing 0 peration completed.There was a stress reduced zone occurred and the ground stress was lower than before the fracturing operation completed.There was a stress incre ased zone occurred in a zone beyond the fractured borehole radial over 15 m.Thus the seam stress around the fracturing borehole had a migration to outward.Within th e pressure reduced zone of the seam, the drilling operation could be conducted smoothly and there was no abnormal occurred when the drilling depth was over 100 m. But within the stress increasing zone along the two sides, there would be serious coal and gas jettings from the borehole occurred when the drilling operation reached a t 2430 m.