Research On The Extremely Close Coal Seam Group On Mining Roadway Optimization Arragement And Mining Sequence

During the process of extremely close thin coal seam mining, the mining of arrange tunnels, support and the sequence choice section mining seriously influence mine pressure, therefore, the rational choice for roadway position, the supporting method and the roadway mining sequence section are of great significance for guiding production safety mine. This test based on Xuyong coal mining strata, geological structure, coal and coal seam roof and floor nature of geological material, comprehensive consideration of the roadway mining pressure coal mining method, appeared rules, the extraction process, the field production system needs, convenient and reliable and construction factors, such as the content, and through the field research, theoretical study and comparative analysis and numerical simulation and many kinds of means, get some results as follows:1) Parameters test using MTS815 rock mechanics test system, do the physical mechanical on mining coal rock strata. Combining with the investigation and analysis, we got that partial of old top rock seam C19 intact, is medium risk falling roof floor rock intact, bottom some general lighter, local phenomenon is stronger; C20 coal seam is complete, is medium rock bottom at fell roof, poor stability, easy to soften, some with mild bottom; C24 coal seam rock medium complete, quality is good, floor rock, not normally bottom relatively complete with mild bottom some or some phenomena.2) Through the observation on the field S11246 segment entry mine pressure, 3 stations for average subsidence shorter is 7.70 mm, highly average subsidence is 11.58 mm, therefore, the program for choosing bolt-mesh-anchor can meet roadway supporting demands.3) Presents two projects on mining scheme: the projectâ… : Multi-joint seam roadway layout, three rock climbing up, lane arranged by horizontal sections;â…¡: Multi-joint seam roadway layout, a coal two rock climbing up, Section of the layout using the wrong type Lane. The layout of mining tunnels choice using qualitative analysis and the system engineering multi-objective decision analysis, both methods get that:â… is better thanâ…¡solution scheme.4) Numerical simulation using FLAC software for a very close numerical simulation of tunnel support. Studied 5m, 10m, 15m and 5m Pillar gangue filled gob with programs such as stress and rock deformation and failure of law. Research shows that, for such 15m pillar, 10m roadway influence changed; At anchor nets cable combination supporting premise, gangue zone as lane was beside filling comply with engineering requirements, and bolting lane of numerical analysis by filling, theoretically proved support scheme is reasonable.5) Determined by determining the ratio between the coal seams mined mining sequence selection descending, On this basis, by numerical simulation analysis section S12 mining area between the mining sequence, drawn the order of mining exploitation is down-type.