Deformation mechanism and control of roadway under close-range goaf considering changes in roof occurrence
In response to the serious deformation of the surrounding rock of the roadway under close-range goaf,the No.2097W working face of Qianjiaying Coal Mine was taken as the background,and the numerical simulation was used to elucidate the characteristics of the roadway pressure manifestation under the change of roof occurrence.The results show that the subsidence of the roof is positively corre-lated with the thickness of the direct roof mudstone,and negatively correlated with the strength of the direct roof rock.As the thickness of the direct roof mudstone becomes thinner,the roof is alternately affected by shear and tensile failure,and the stability of the roof de-creases with the weakening of the direct roof strength.Under stress disturbance,internal cracks in the rock mass expand upwards,and zoning failure occurs at weak interlayer surfaces.The plastic circle range increases,and the overall failure mode is complex;further-more,it is proposed to use high pre-tensioning thick layer anchoring technology to maintain and control the roof,construct a low-damage and small deformation steady-state anchoring rock beam,design support parameters,and conduct industrial experiments.The results of mine pressure monitoring show that the roadway control effect is good.
万方数据
维普
