Study on regional mine pressure behavior law of weak roof and floor working face in large dip coal seam and large mining height stope

In order to study the law and characteristics of mine pressure behavior in the normal zone, transition zone and pressure relief zone of 1305S working face under the complex mining geological conditions of weak roof and floor of large dip angle and large mining height in Changcheng No.2 Coal Mine, Inner Mongolia, a numerical simulation model of sliding filling of caving rock block in inclined coal seam goaf is established, and the research method combining numerical simulation and field measurement is adopted. The research results show that along the inclined direction, the vertical stress in the middle and upper parts of the 1305S working face show the characteristics of transition zone>normal zone>pressure relief zone, and the lower part of the working face shows the characteristics of pressure relief zone>transition zone>normal zone. During the advancing process of the 1305S working face, the average periodic weighting step distance is 13.3 m, and the working resistance of the support is between 26.75 MPa and 33.05 MPa during the periodic weighting. The vertical stress of the roof along the inclined direction of the working face generally shows the characteristics of the upper part of the working face>the middle part>the lower part; the deformation of the side wall on one side of the working face of the roadway is large. The field measurement results show that the maximum displacement of the roof monitoring of the return airway is 860.18 mm, and the maximum displacement of the roof monitoring of the transportation roadway is 367.84 mm. The displacement of the surrounding rock of the two roadways shows the characteristics of the return airway>the transportation roadway.