The Impact Studies Of Fracture Structure On The Coal Pillar Stability And Supporting Of Roadway Driving Along Next Goaf

Roadway driving along next goaf, a main decorate a form of mining roadway, is widely used in all types of coal mine. The stability of narrow coal pillar in roadway driving along next goaf and roadway supporting technology are the research difficulty for domestic and foreign scholars. 603 working face of Qujiang mine is the engineering background in this paper, using theoretical analysis, numerical simulation and field tests a combination of methods, this article analyzes the basic roof rupture influence on narrow coal pillar in roadway driving along next goaf, and to conducted a comprehensive study about roadway supporting technology in roadway driving along next goaf.Establish the structural mechanics model of roadway surrounding rock, the principle of mechanics deriving the calculation formula coal pillars loads for the basic roof rupture in five different position, the displacement on coal pillar can be reduced by enhanced the supporting strength of the entity coal side and reducing the height of the roadway. Comparing the results show that: the displacement of coal pillar is minimal when the rupture key block can not form an articulated structure; if the basic roof rupture and the key block form an articulated structure, it is the most favorable for the stability of surrounding rock of roadway when key block B rupture on the outside of the coal pillar, and it is the most unfavorable for the stability of surrounding rock of roadway when key block B rupture above the roadway.The deformation and the stress characteristic of narrow coal pillar be simulated by UDEC when rupture five kinds position, and the stability of narrow coal pillar affected by narrow coal pillar width, basic roof thickness, height of roadway and thickness of immediate roof be analyzed. The stability of narrow coal pillar in five different rupture position from big to small were: Outside of the coal pillar(not form an articulated structure), outside of the coal pillar, above the entity coal, above the narrow coal pillar, above the roadway.Several forms of damage in roadway driving along next goaf of Qujiang mine were summarized; put forwarded the support method of high prestress truss and anchor on the basis of original supporting scheme and analyzed support mechanism, the deformation of roadway have been effectively controlled with Truss and Anchor.The rational width of coal pillar is calculated by Numerical simulation and theoretical calculation respectively, the most reasonable width of coal pillar is 5m after comparative; the 603 working face basic roof rupture is on the outside of the narrow coal pillar by rock detection loggers; According to the actual situation of working face 603 of return air roadway, using the joint supporting that "bolt(cable) + metal mesh + truss anchor beam" targeted the top plate based on the original scheme, using the joint supporting that "anchor+ metal mesh + truss anchor beam" on the narrow pillar working slope, the support methods that "bolt + metal mesh + ladder beam" be used on the entity coal working slope, this scheme has made good supporting effect on site.