Study on Mechanism of Strong Strata Pressure in Fully Mechanized Mining Face of Huge Thick Sandstone Formation

Based on the strong pressure of the returning airway in 31102 working face of Nalinhe No.2 well, the theoretical analysis and on-site measurement are used to study the mechanism of strong mine pressure in the fully mechanized mining face of the thick sandstone layer. The research shows that when the 31102 working face enters the double working face squares, the overburden structure of the stope is the standard load three zones structure; based on the double-sided stratum structure of 31102 working face, the mechanical model of the strike bearing pressure is established and the double is obtained. It is concluded that the working face of stage 31102 in double squares is 42.69 m to 215.67 m ahead to reach the stress condition of rock burst; the medium impact hazard range is 57.47 m to 137.02 m, the high stress transmitted by the range “DLZ” in the double squares phase 31102 along the empty roadway is the main reason for the strong occurrence of mine pressure. The strong control mechanism of the 31102 return airway is: to determine the reasonable pressure relief parameters, to release the coal volumetric energy through the large diameter borehole, and minimize the damage to the surrounding rock structure to ensure that the surrounding rock of the roadway is in “low stress-low disturbance” status.