<p>With the increase of mining depth, the problem of large deformation of surrounding rock in mining roadway becomes more serious under high stress and strong mining conditions. In order to prevent significant deformation and other strong dynamic pressures in the mining roadway of an extra-thick coal seam, a novel method based on the integration of deep and shallow combined roof cutting (DSC-RC) technology and high prestress constant resistance (HPCR) support technology is proposed. The DSC-RC technology encompasses two distinct techniques: deep pre-splitting blasting and shallow dense drilling. The deep pre-splitting blasting technology actively controls the collapse location of the overlying rock structure, thereby reducing the cantilever length of the goaf roof and the load of the overlying rock transmitted to the roadway sides. This results in the optimization of the roadway stress environment. The shallow dense drilling technology can cause the expansion and connection of cracks between the holes, forming a shallow cutting line that breaks the rock layer. The two roof cutting technologies are mutually reinforcing, hastening the collapse of the roof, and exploiting the support effect of the roof caving gangue after crushing and expansion, thereby reducing the pressure on the front of the working face and the solid coal sides. Concurrently, HPCR support technology uses CRLD anchor cables to ensure the stability of the roadway roof during blasting. The comprehensive evaluation value of surrounding rock stress is used to analyze the effect of roof cutting and pressure relief. Through numerical simulation, the influence of roof cutting parameters on the roadway is analyzed. The stress evolution law of surrounding rock under different roof cutting parameters is obtained, and the advantages of roof cutting are verified. The surrounding rock stress in the original stress peak area is obviously reduced after roof cutting, and the stress peak position is obviously far away from the roadway. The field data verified the effectiveness of the new method. The pressure of hydraulic support in the working face, the pressure of advanced hydraulic single support in the roadway, and the deformation of surrounding rock were significantly reduced. The results of the research may provide a new approach to the control of the surrounding rock in extra-thick coal seams under the influence of mining.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

A Novel Method of Deep and Shallow Combined Roof Cutting and Constant Resistance Support for Enhancing Deep Mining Roadway Stability

  • Xiaoming Sun,
  • Ming Jiang,
  • Tong Zhang,
  • Chengyu Miao

摘要

With the increase of mining depth, the problem of large deformation of surrounding rock in mining roadway becomes more serious under high stress and strong mining conditions. In order to prevent significant deformation and other strong dynamic pressures in the mining roadway of an extra-thick coal seam, a novel method based on the integration of deep and shallow combined roof cutting (DSC-RC) technology and high prestress constant resistance (HPCR) support technology is proposed. The DSC-RC technology encompasses two distinct techniques: deep pre-splitting blasting and shallow dense drilling. The deep pre-splitting blasting technology actively controls the collapse location of the overlying rock structure, thereby reducing the cantilever length of the goaf roof and the load of the overlying rock transmitted to the roadway sides. This results in the optimization of the roadway stress environment. The shallow dense drilling technology can cause the expansion and connection of cracks between the holes, forming a shallow cutting line that breaks the rock layer. The two roof cutting technologies are mutually reinforcing, hastening the collapse of the roof, and exploiting the support effect of the roof caving gangue after crushing and expansion, thereby reducing the pressure on the front of the working face and the solid coal sides. Concurrently, HPCR support technology uses CRLD anchor cables to ensure the stability of the roadway roof during blasting. The comprehensive evaluation value of surrounding rock stress is used to analyze the effect of roof cutting and pressure relief. Through numerical simulation, the influence of roof cutting parameters on the roadway is analyzed. The stress evolution law of surrounding rock under different roof cutting parameters is obtained, and the advantages of roof cutting are verified. The surrounding rock stress in the original stress peak area is obviously reduced after roof cutting, and the stress peak position is obviously far away from the roadway. The field data verified the effectiveness of the new method. The pressure of hydraulic support in the working face, the pressure of advanced hydraulic single support in the roadway, and the deformation of surrounding rock were significantly reduced. The results of the research may provide a new approach to the control of the surrounding rock in extra-thick coal seams under the influence of mining.