Mine pressure behavior of shallow buried super long working face
In order to study the mine pressure behavior of shallow buried super long working face,the 5-20311 working face of Qinglongsi Coal Mine is taken as the research background,and the mining simulation analysis is carried out using FLAC3D software,and the change law of roof overburden displacement,surface subsidence,crack,vertical displacement and working resistance of hydraulic support along with the mining advance distance are studied.The roof overburden of shallow buried super long working face is prone to the phenomenon that the direct roof cuts off along the full thickness of the coal wall,and the whole step subsidence occurs on the surface.During the mining process of 5-20311 working face,the first weighting step of roof overburden is about 24 m,the periodic weighting step is about 16~24 m,the average periodic weighting step is about 20 m,the average development height of conducting fracture zone is about 50 m,and the maximum development height is a-bout 72 m.When the mining advance distance is 24 m,the vertical displacement and working resistance of the hydraulic support in the working face reach the maximum,which are 320 mm and 40.5 MPa,respectively.When the mining distance of the working face is greater than 24 m,the vertical displacement and working resistance of the hydraulic support start to change periodically with the change period of about 16~24 m.
shallow buriedsuper long working faceFLAC3Dsurface subsidencefissureworking resistance