Research On New Technologies Of Multiple Combined Support In North-aisle Roadway Of Dongtan Coal Mine

The roadway support problems have always been an important factor influencing the efficiency of coal mines.To ensure a steady increase in coal mine production and to overcome deep mine natural disasters,deep roadway support is an important part.The difficulties in roadway support stability caused by mining in deep mines are the common problems in today's world roadway support.In this paper,the deformation of surrounding rock of roadway is clarified by analyzing the geological conditions of the roadway,combined with theoretical research and on-site detection.A new method of multi-joint support was proposed for the conditions of deep-well soft rock in the north track.The feasibility of the support method was determined by numerical simulation and experimental research.The use of multiple joint support technologies has effectively controlled the long-term deformation and repeated repairs of the north-aisle lane of the Dongtan Mine,resulting in higher roadway stability,reduced number of repetitive repairs,reduced support costs,and ensured the safety and efficiency of the mine.produce.This paper obtained the following main results through research:By analyzing the geological conditions of the Dongtan coal mine and the original supporting forms of the test roadway,the influence of roadway surrounding rock structure and mining stress on roadway deformation is introduced,and the complexity of roadway surrounding rock stress is analyzed;The main reasons for the difficulty in softening and supporting the surrounding rock of large lanes are the muddy soft rock and the dynamic pressure effect of multiple cross-cuts.For the deep high concentration stress and dynamic pressure effects,the pressure relief technology for the roadway pressure relief tank was proposed.The pressure relief groove is located in the stress concentration area of the surrounding rock.After the excavation,the pressure relief groove is deformed(reduced in space)under the action of concentrated stress,and the surrounding rock in the vicinity of the stress relief groove generates a certain amount of expansion deformation,which in turn causes certain cracks in the surrounding rock.Therefore,a certain amount of stress(energy)can be released and sustained.At the same time,the high stress concentrated area of the roadway is transferred to the deep part of the roadway so that the stress around the roadway can enter a relatively stable stage.Aiming at the problem of large deformation of roadways,multiple joint support systems for tough seal,pressure-controlled cementation,and sustained-release superimposed stress(spray,anchor,rope,double-spray,injection,injection,and re-combination)were proposed to realize each The coordination between the supporting bodies of the grade achieves the best effect of continuously increasing the strength of the soft rock body and the self-repair of the supporting body.The use of new grouting anchor grouting to fill the surrounding rock cracks with multi-anchor shotcrete support can form a multi-layer effective composite arch,composite arches in the compression zone of anchor rods,and strong reinforcement arches formed by steel ropes as bones and slurry cementing surrounding rocks.Therefore,the effective bearing range of the supporting structure is expanded,and the integrity and bearing capacity of the supporting structure are improved.The support technology is applied through on-site testing to effectively control the deformation of the surrounding rock in the north track,ensure the long-term stability of the roadway,and have a good application effect.