Research on stress distribution law of two ribs in large dip angle workingface under influence of dynamic and static loads

In order to study the maximum principal stress distribution characteristics of the roadway and return airway ribs under the influence of dynamic and static loads, a numerical simulation of the Flac3D numerical model with a tilt angle of 37° was established based on the geological conditions of the No.1132 working face of Bostan Coal Mine in Xinjiang. The results show that the maximum principal stress distribution of the large dip angle working face is asymmetric under the influence of static load. The two sections of the transportation roadway and the return airway were characterized by the lower left high stress area and the right upper high stress area. Under the influence of dynamic and static loading, the maximum principal stress fluctuation of the roadway was larger than that of the return airway. The maximum principal stress of the left rib of the transportation roadway and the return airway was increased, the maximum principal stress of the right rib was reduced, the maximum principal stress distribution of the roadway rib was reduced, and the maximum principal stress distribution of the roadway rib was more asymmetrical than under static load.According to the maximum principal stress distribution characteristics of the roadway ribs of the large dip angle working face, the large-diameter drilling pressure relief measures were optimized. After the on-site cuttings inspection, the amount of cuttings in the transportation lanes were reduced by 11.8% on average. The amount of cuttings were reduced by 16.5% on average, and the pressure relief effect was good.