Research On Full Anchor Cable Support Technology For Roadway Roof In Loose And Extra Thick Coal Seam In Hujiahe Coal Mine

The roof of the roadway in loose and extra-thick coal seams is a weak coal body with poor stability and high degree of fragmentation and swelling.After excavation,a large range of plastic damage areas occur,and the weak bearing capacity of the roadway roof leads to accidents such as collapse or wall fragmentation that are prone to occur during roadway service,seriously threatening the safety of workers.Therefore,the deformation and damage mechanism of the surrounding rock in loose and extra-thick coal seams is explored and reasonable roof support schemes are designed,Ensuring the safety of roadway roof in extremely thick coal seams is crucial.This thesis takes the transportation roadway of 401110 working face in Hujiahe loose and extra thick coal seam as the research object,using the methods of on-site investigation,theoretical analysis,numerical simulation,and engineering tests to analyze the deformation characteristics of surrounding rock and roof failure mechanism of the roadway in extra thick coal seam,study the full anchor cable support technology and mechanism of the roadway roof in loose and extra thick coal seam,and conduct onsite application of the transportation roadway in 401110 working face in Hujiahe Coal Mine to verify the effectiveness of the full anchor cable support scheme for the roadway roof,The conclusions are as follows:1)The deformation characteristics of surrounding rock in loose and extra-thick coal seam roadway in Hujiahe Coal Mine and the factors affecting the stability of roadway roof were studied.Based on the geological characteristics of transportation roadway in 401110 working face,a numerical simulation model was established.Through analyzing the displacement and stress nephogram of surrounding rock in unsupported loose and extra-thick coal seam roadway,the mechanism of damage and development of the plastic zone of roadway surrounding rock was explored,and the poor stability of the roof in extra-thick coal seam in 401110 working face was revealed The bearing capacity is weak,and the plastic failure zone is large.2)The full anchor cable support technology and mechanism of roadway roof in loose and extra-thick coal seams are studied.Establish a control idea for roadway roof in loose and extra-thick coal seams,analyze the impact of different support methods on roadway roof stability within the range of shallow surrounding rock in the roadway roof,propose ladder support for roadway roof in loose and extra-thick coal seams and a new type of "four high" anchor cable support technology,clarify the mechanism of full anchor cable support for roadway roof,and obtain a long-term active support system for roadway roof in loose and extra-thick coal seams.3)Designed the full anchor cable support parameters and schemes for the roof of the transportation roadway in the 401110 working face,using numerical simulation methods,compared and analyzed the distribution of the effective stress field of the anchor cable under different support parameters,selected the reasonable parameters for the roof support scheme of the transportation roadway in the 401110 working face,and proposed a support scheme suitable for the roof of the roadway in the loose extra-thick coal seam of Hujiahe Coal Mine.Through simulation and comparison of the plastic zone,displacement,and stress nephogram under different support schemes,The feasibility of the full anchor cable support scheme is confirmed.4)Field application of the transportation roadway in the 401110 working face of Hujiahe Coal Mine was conducted to verify the effect of the full anchor cable support scheme for the roadway roof.Select a suitable test roadway section to establish a mine pressure observation station,monitor and collect deformation data of roadway surrounding rock,and conduct boreholes to peek,summarize deformation laws of roadway surrounding rock,and verify that the full anchor cable support scheme can effectively reduce roadway roof subsidence and the degree of breakage of both sides of surrounding rock,meeting the production requirements of 401110 working face transportation roadway.This thesis has 59 drawings,7 tables,and 81 references.