Study On The Weak Bonding Of Thick Coal Seam Fully Mechanized Coal Caving Section Coal Pillar

Studied the main mining layer6#coal belonging to the west in a coal mine in this paper, The coal seams belonging to the Carboniferous、Upper Permian Series Taiyuan Formation。The seam has an average thickness of17.5m, buried depth538m, coal seams buried deeper。 Combined with the low strength of the roof strata and the low maturity of roof strata and coupled with the Roof multi argillaceous, calcareous cemented filling。 the roof strata Affected by late tectonic stress, forming a fissure-dual porosity media。 Therefore, lead to Structure of the low intensity of the roof strata and Poor cementation degree。 After rock contact with water softening deformation or even disintegration, The roof is weak bonding of roof。Research Less the process parameters of fully mechanized caving mining and overlying strata movement under circumstances of Such mining depth conditions and weak bond roof case the In the past。In this paper, based on a detailed understanding and analysis of the results of previous studies, use theoretical analysis, FLAC3D numerical simulation and field measurement combining a variety of research methods.。In-depth study on the weak bonding of thick coal seam fully mechanized coal caving section coal pillar。Taking the geological condition of a mine in east as the background, Aiming at the weak binding coal seam roof, thick characteristics, analysis on the stress state of the solid coal roadway and goaf roadway, the internal stress distribution of coal pillars, The content of the whole process of deformation and the influence of section coal pillar stability factors. Combined with the mature coal pillar width calculation the theoretical formula, Estimates of the mine6101working face coal pillar width range of16-28m.The numerical simulation for the solid coal roadway show that effects of solid coal roadway affected by stope face is relatively simple, the structure of surrounding rock is stability and roadway surrounding rock deformation is small before the50m coal mining face. The deformation of roadway surrounding rock become intensification on the50m coal mining face. Working face into the cycle pressure and the deformation of roadway surrounding rock stability with continue to promote the working face.Through the Flac3D numerical simulation to make fully mechanized top coal caving model that setting with different width of coal pillar,study on the pillar stress, deformation of surrounding rock of roadway surrounding rock, and the plastic zone of pillar. The results show that coal pillar can be in a stable state and the roadway surface deformation when the width of coal pillar is16m-24m. Reasonable coal pillar pillar width to improve the coal recovery rate...