No.3 coal seam 32501 comprehensive mining face is located below the No.2 coal seam hollowing area at the position of 4.3～7.9 m.The roadway of the face is affected by the overlying hollowing area,which leads to greater difficulty in controlling the deformation of the surrounding rock.The theoretical method is used to calculate the maximum damage depth of the bottom plate after No.2 coal seam is mined back,and it is analysed that No.2 coal seam will break the integrity of the top plate of No.3 coal seam,leading to the top plate crushing,which will bring constraints on the control of perimeter rock of the roadway of face mining back.Combined with the shallow depth of No.3 coal seam,the geological stress is not obvious and the geological structure of the mining area is simple,it is proposed to use anchor net rope to support the surrounding rock,the top plate is supported by high-strength anchors+short anchors,the shoulder of the roadway gangs is strengthened by high-strength long anchors to avoid the roadway gangs from gangs,and the auxiliary use of metal nets and W steel belts is used to increase the strength of the surface protection.After the field application,32501 comprehensive mining face perimeter rock deformation in a small range,to achieve the near coal seam mining hollow area under the broken roof plate back to mining roadway perimeter rock deformation effective control.
roadway excavationclose coal seam groupbroken roof plateroadway support
NETL
NSTL
万方数据
