中国矿山工程

In this study, the numerical model of the drill hole is constructed, and the depth of burial is used to characterize the overall stress level of the borehole, to investigate the stress distribution characteristics around the borehole under different burial depths, to elucidate the time-varying characteristics and distribution of the displacement around the borehole, and to reveal the influence of the depth of burial on the development of the cracks around the borehole. The results show that the stress concentration phenomenon occurs after the stress field of the coal around the drill hole is adjusted. With the increase of burial depth, the stress around the drill hole gradually increases, and the range of stress concentration area is increasing. The deformation of the coal body around the hole has a certain direction, and the deformation of the coal body will be larger along the straight line direction, and the perpendicular direction to this straight line will have a smaller deformation. With the increase of burial depth, the deformation of coal around the borehole increases. There is a certain correspondence between the development of fissures and the deformation around the coal. With the increase of burial depth, the development of fractures is gradually obvious, and the distribution is characterized by concentration in the middle and dispersion around.