Aiming at the surrounding rock control problem of mining and preparation entries in Xingdong mine with large mining depth, and the comprehensive control countermeasures including high pre-stress cable truss system, th...Aiming at the surrounding rock control problem of mining and preparation entries in Xingdong mine with large mining depth, and the comprehensive control countermeasures including high pre-stress cable truss system, this study put forward powerful anchor support system and anchor cable adaption technology to surrounding rock deformation. Furthermore, the control measures possess the supporting performance with ‘‘primary rigid-following flexible-new rigid, and primary resistance-following yield-new resistance'', which suits deep roadway surrounding rock control. The mechanical model of truss anchor supporting roof beams was established, and the inverted arch deflection produced by the cable pre-stress with stress increment effect and roof beam deflection were obtained. And then the system working mechanism was illustrated. Finally, the surrounding rock support parameters were determined by means of comprehensive methods, and put into practice. The results show that surrounding rock deformation realized secondary stability after three months. The roadway sides convergence value was less than 245mm, and roof subsidence was less than 124mm. In addition, there was no expansion and renovation during service period.展开更多
This paper focuses on anisotropy of coal permeability and its stress sensitivity.Coal blocks were taken from Xinjing Coal Mine in Yangquan Coal District.Coal cores were then drilled along the strike,dip,and vertical d...This paper focuses on anisotropy of coal permeability and its stress sensitivity.Coal blocks were taken from Xinjing Coal Mine in Yangquan Coal District.Coal cores were then drilled along the strike,dip,and vertical directions.Coal permeabilities were measured with respect to stress by using a self-developed coal permeability measurement system.The used samples exhibited significant permeability anisotropy.The permeability along the strike direction was greatest among the three directions,the permeability along the vertical direction was the smallest,and the permeability along the dip direction was between the other two directions.The sensitivity of coal permeability to stress was transversely isotropic.The stress sensitivity coefficient was greater along the horizontal directions than along the vertical directions.Coal permeability exhibited anisotropic stress sensitivity due to anisotropy in Young’s modulus and porosity.The results obtained in this study are useful for optimizing the arrangement of pre-drainage boreholes.展开更多
基金provided by the National Natural Science Foundation of China(No.51234005)National Basic Research Program of China under Grant(No.2010CB226802)Fundamental Research Funds for the Central Universities(No.2010QZ06)
文摘Aiming at the surrounding rock control problem of mining and preparation entries in Xingdong mine with large mining depth, and the comprehensive control countermeasures including high pre-stress cable truss system, this study put forward powerful anchor support system and anchor cable adaption technology to surrounding rock deformation. Furthermore, the control measures possess the supporting performance with ‘‘primary rigid-following flexible-new rigid, and primary resistance-following yield-new resistance'', which suits deep roadway surrounding rock control. The mechanical model of truss anchor supporting roof beams was established, and the inverted arch deflection produced by the cable pre-stress with stress increment effect and roof beam deflection were obtained. And then the system working mechanism was illustrated. Finally, the surrounding rock support parameters were determined by means of comprehensive methods, and put into practice. The results show that surrounding rock deformation realized secondary stability after three months. The roadway sides convergence value was less than 245mm, and roof subsidence was less than 124mm. In addition, there was no expansion and renovation during service period.
基金funding support of the State Key Research Development Program of China (Nos. 2016YFC0600708 and 2016YFC0801402)
文摘This paper focuses on anisotropy of coal permeability and its stress sensitivity.Coal blocks were taken from Xinjing Coal Mine in Yangquan Coal District.Coal cores were then drilled along the strike,dip,and vertical directions.Coal permeabilities were measured with respect to stress by using a self-developed coal permeability measurement system.The used samples exhibited significant permeability anisotropy.The permeability along the strike direction was greatest among the three directions,the permeability along the vertical direction was the smallest,and the permeability along the dip direction was between the other two directions.The sensitivity of coal permeability to stress was transversely isotropic.The stress sensitivity coefficient was greater along the horizontal directions than along the vertical directions.Coal permeability exhibited anisotropic stress sensitivity due to anisotropy in Young’s modulus and porosity.The results obtained in this study are useful for optimizing the arrangement of pre-drainage boreholes.
