Extra thick high roof cutting roof self-formed roadway surrounding rock control technology
In order to solve the problems such as low coal recovery rate,mining continuing tensely,coal column stress concentration,and difficulty of roadway support with the traditional coal retention pil-lar and gob-side entry retaining,East Second Mining 120313 working face of Xiangshui Coal Mine is taken as the research object,and the active support parameters,roof blasting parameters,stop bar pa-rameters and temporary support parameters are determined through the force analysis and calculation of the mechanical model of the surrounding rock failure mechanism of the short arm beam roof,and FLAC3D numerical simulation analysis of roadway roof cutting pressure relief effect,and the research process of field experiment.The stability control technology of surrounding rock of the extra thick upper roof of the roadway of medium thick coal seam that"constant resistance large deformation anchor cable+bidirectional presplitting blasting of roadway roof+roadway reinforcement support+flexible U-shaped steel stop bar+temporary support of single hydraulic pillar"is proposed.The results show that the maxi-mum value required to compensate the supporting force of a single constant resistance large deformation anchor cable of the extra thick upper roof plate is 309 kN according to the mechanical properties of the roof.Compared cut and uncut roof of return air roadway,the maximum value of the leading supporting pressure of the working face is reduced by 15％,and the maximum value of the lateral support pressure of the roadway is reduced by 27％in the case of cutting the top;the deformation of the roadway is effec-tively controlled,and the surrounding rock of the roadway tends to be stable within the range of 160-175 m after the lagging working face.The coal recovered is 13.44 ton per unit column length of the working face,which improves the coal recovery rate of the section and reduce the mining costs.
short arm beamcompensation supportcutting the roof and pressure reliefnumerical simulationstability of surrounding rock
万方数据
维普
