Study on deformation mechanism and support technology of dynamic pressurized gateway in deep soft seam

In order to solve the high deformation,complicated deformation mechanism and hard maintenance problems of the mine deep dynamic pressurized roadway in Xinzhi Mine,the paper analyzed the deformation features of the mine roadway,measured and tested the geological mechanics parameters of the surrounding rock in the mine roadway and numerically simulated the stress distribution condition in the coal pillar. Thus the paper provided the open and no support roof distance and the open an d no support sidewall distance to be reduced,the support strength of the sidewall and the support technology of the surface protection capacity. The site experiment results showed that the deformation mechanism of the dynamic pressurized roadway in the deep soft seam was the deep depth of the mine roadway,high geostress,low loading for ce of the soft and broken coal in the sidewall,the no stop of the rock strata movement occurred by the mining near the heading face,continued variation of the stress in the surrounding rock of the mine roadway,insufficient support strength of the sidewall, no loading structure formed at the shallow part of the sidewall and the interaction betwee n the sidewall convergence and the floor heave. The stress in the coal pillar with a distance of 2.48 m to the edge of the mine roadway was in the stress peak and was 2.2 2 times higher than the in- situ stress. After the new support design applied to the underground mine,the deformation value of the mine roadway was reduced over 80%.