Surrounding rock deviatoric stress difference evolution and control of gob-side entry driving in deep mining

Taking the deep water-high filling face in Xingdong mine as the engineering background, the evolution law of the maximum principal deviatoric stress and the plastic zone in the gob-side entry driving are simulated in the process of exploited height from 3.0 m to 5.0 m with FLAC^3Dsoftware.Analysis results show that:there is a peak deviatoric stress band in integrated coal beside the roadway, and the peak deviatoric stress area of the coal pillar is located from 3.0 m to 4.0 m, and the lower left side and the upper left side of the roadway have a low value of deviatoric stress; with the increase of mining height, the peak area and the peak value of the deviatoric stress in the coal pillar gradually decrease, while the peak value of the deviatoric stress in integrated coal beside the roadway tends to expand towards the right side; in the process of increasing mining height, the scope of plastic zone of roadway surrounding rock gradually increases, and the direction of its enlargement is consistent with the direction of peak deviatoric stress band expansion.Accordingly, a high pre-tension and powerful supporting system is proposed to control the gob-side entry driving in the deep filling mining face, and combined with the characteristics of the deviatoric stress distribution to determine the reasonable support parameters.Field application proves that the technology can effectively controls the deformation of surrounding rock and realize the stability of gob-side entry driving under deep filling mining conditions.