Study On The Roadway Stability Control Of Fully-mechanized Top-coal Caving Long-wall Face In Soft And Thick Coal Seam

The gate surrounding rocks of long-wall face has been a hot problem that people want to solve over the years, especially that of the gate with broken roof and floor in soft coal seams is one of the difficult problem that obstruct safe and efficient production. Treated the gate of 4302 working face in 3# coal seam in Changping Coal Co. Ltd. industry limited company as engineering background and based on the wholly analyses of the current technology and engineering application about fully-mechanized long-wall mining face domestic and overseas, the stability of the gate of fully-mechanized top-coal caving long-wall face in soft thick coal seam has been researched by the using of theoretical analysis, finite element method and field test.Specific to the complex geological condition of gate adjoiningrock working face, Mastered the distribution of face support pressure around long-wall and pressure behavior of crossheading under influence of mining mine according to mine pressure observation of 4302 working face. The Mechanism of crossheading stability impact by fully mechanized caving in the soft thick seam has been revealed; The theoretical analysis and the numerical simulation were applied to analyze to the relation between anchor body strength and amid surrounding rock's stress, displacement, and discuss combined action principle of supports and surrounding rocks; Revealed the discipline of crossheading stability on coal pillar according to different coal pillar width on working face confining pressure behavior of crossheading; Through analyze the failure mechanism and structural feature of mine pillar and upside rock, the reasonable virgin coal width formula has been obtained.Through all research above, The stable control's key technological approaches of roadway nearby fully-mechanized top-coal caving face in soft and thick coal seam was obtained,"keep reasonable width of pillar mining +associated supporting of low-preload and high strengthen bolting nets +surrounding ground grouting in bad region by mining excavation or partly reinforced support by short anchor cable".It was succeeded in practical application. It is an useful exploration for the roadway stability control of fully-mechanized top-coal caving long-wall face in soft and thick coal seam.