1. Formation mechanism and evolution laws of gas flow channel in mining coal and rock.
- Author
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ZHANG Yong, XU Li-feng, LIU Ke-ming, LI Yan-jun, ZHANG Bao, and LI Wei-bin
- Subjects
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GAS flow , *GAS extraction , *COAL mining , *ROCK mechanics , *DEFORMATIONS (Mechanics) - Abstract
In order to study the formation mechanism and evolution laws of gas flow channel in mining coal and rock, using relevant theories of fracture mechanics and rock mechanics with combinations of mining coal and rock's crack development characteristics, the gas flow channels in mining coal and rock ahead of working face were divided into isolated channel area, tensile fracture failure area, shear failure area,and failure area after abutment pressure peak. And according to the developmental process of crack in mining coal and rock and formation mechanism of gas channel in different areas, it's concluded that the first three areas belong to mesoscopic channels, and the fourth area belong to macroscopic channels. According to the relevant theories of material mechanics and deformation and mechanics characteristics of coal roof, crack developmental process and channel conduction property during mining process, roof macroscopic gas channels were divided into three areas from above to below; gas turbulent channel area, gas transition flow channel area and gas seepage channel area, and combined with simulation in laboratory, the development process of gas channel in overlying coal (rock) seams were analysed, which experienced the process of decompression, instability, crack initiation, mutation splitting, anastomosis contraction, accelerated closed, channel preservation, accelerated closed again and compaction closed completely. [ABSTRACT FROM AUTHOR]
- Published
- 2012