The Strata Behaviors Characteristics And The Determination Of Reasonable Malposition Of Simultaneously Mined Face In The Close Distance Coal Seams

Close distance coal seam occurrence are widely in our country,more and more people has drawn great attention of its mining problem.But there is a little of the research findings of close distance coal seam mining technology, main is the summary of the practical and empirical.According to the huayuan close with coal mining working face actual conditions,apply to the theoretical analysis, numerical simulation and strata behaviors methods,reasonable of close distance coal seam mining working face position,between the layers with working face bed rock of complex stress field,voltage stability,strata behaviors are studied, draw conclusions:1)According to theoretical analysis and numerical simulation has obtained that the close distance coal seam of the upper coal seam has mined, the damage to the floor stress transfer law,stress distribution characteristics.Combined with huayuan actual situation is obtained that its impact has been extended to the lower coal seam.when the upper coal seam has mined.2)According to theory of the working face layout in the reduced pressure zone,establisheda close the simultaneous mined model, calculated the reasonable working face position;On the basis of stability area of working face layout, Considering the upper coal seam floor stress and the lower coal seam abutment stress are overlay that obtained with the range of reasonable position in the close mining of coal seam.Through two kinds of scheme comparison and analysis, determine the huayuan close coal seam with simultaneous mined face reasonable position.3)Using the FLAC3D numerical simulation research for close the distance coal seam surrounding rock stress field stope roof stability affect the choice of the reasonable face position,also verified theoretical analysis is rationality.4)According to the huayuan close with coal mining working face actual conditions,apply to the strata behaviors methods,Came to a close distance coal seam simultaneous mined process with strata behaviors characteristics and regularity of the upper coal seam and the lower coal seam.For the study of lower coal seam structure and stope wall rock control provides a reliable data support.Above all research achievements,we basically solved the close distance coal seam group with some practical problems in simultaneous mining,Similar in the future under the condition of close distance coal seam mining,provides scientific basis for its have certain guiding significance.