Study on Mine Earthquakes Mechanism and Ground Vertical Well Hydraulic Fracturing Shock Absorption in Thick Hard Rock Mine

Mine earthquakes are serious disasters in coal mines, especially extremely thick hard strata. This study investigates the occurrence mechanism of fracture-type mine Hydraulic fracturing by ground vertical well was used for shock absorption. Dongtan taken as a case study. Field investigation, theoretical analysis, industrial tests, and field monitoring were revealing mechanism. First, mechanical model thick, strata under horizontal concentrated stress established. The fracture step equation energy release rock derived semi-inverse solution variational method. Then, after hydraulic relationship between spacing maximum magnitude deduced. 6306 working face designed controlling earthquake magnitude. Results show that increases breaking distance layer led to an increase released during fracture, enhancement earthquake. By applying technology using shaft, frequency total above 1.5 ML decreased 54.55% 81.22% than 6304 face, reduced 70% 84.98% 6305 face. can significantly reduce However, it not prevent control back-transition slip-type earthquakes. obtained results provide basis absorption mines with super-thick