(1. School of Mechanics and Civil Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;
2. State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China)
Abstract:In order to investigate the effect of the effective stress on deformation and permeability of coal,the strain and permeability of coal cores from No. 9 coal seam of Zhaogezhuang Coal Mine in Kailuan Mine area were measured with the triaxial servo-controlled seepage device. The experiments were carried out under two types of conditions. One type of condition was to reduce the inlet gas pressure while the confining stress was kept constant. Another type of condition was to reduce the gas pressure and confining stress synchronously. The coal shrinkage was found to increase with the effective stress. There was a linear correlation between the volumetric strain of coal and the effective stress within the range of 5.2 MPa and 6.5 MPa. When the effective stresses were outside the range,the stress-strain lines were not straight anymore,and coal dilatation was observed from some samples. The gas flow velocity decreased with the decreasing of gas pressure of inlet port. However the coal permeability increased regardless the decreasing or increasing of effective pressure. Therefore the effect of gas slippage should be considered when the coal permeability change with effective stress is investigated.
HUY P Q,SASAKI K,SUGAI Y,et al. Carbon dioxide gas permeability of coal core samples and estimation of fracture aperture width[J]. International Journal of Coal Geology,2010,83(1):1-10.
[8]
曹树刚,李 勇,郭 平,等. 瓦斯压力对原煤渗透特性的影响[J]. 煤炭学报,2010,35(4):595-599.(CAO Shugang,LI Yong,GUO Ping,et al. Effect of gas pressure on gas seepage of outburst coal[J]. Journal of China Coal Society,2010,35(4):595-599.(in Chinese))
[11]
许 江,张 敏,彭守建,等. 不同温度条件下气体压力升降过程中瓦斯运移规律的试验研究[J]. 岩土力学,2016,37(6):1 579-1 587. (XU Jiang,ZHANG Min,PENG Shoujian,et al. Experimental study of migration laws of gas during loading-unloading process at different temperatures[J]. Rock and Soil Mechanics,2016,37(6):1 579-1 587. (in Chinese))
[12]
HARPALANI S,CHEN G. Influence of gas production induced volumetric strain on permeability of coal[J]. Geotechnical and Geological Engineering,1997,15(4):303-325.
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