摘要
煤体变形和瓦斯渗流的耦合作用是煤矿瓦斯突出机理研究中的重要问题,煤渗透率的变化与其应力状态密切相关。为了理清有效围压对煤体渗透性的影响,对煤样进行了不同瓦斯压力下全应力应变过程的渗透性实验,分析了瓦斯压力对煤样强度和渗透率的影响;针对不同瓦斯压力,设计完成了相同有效围压下三轴压缩力学实验(无瓦斯作用);并利用孔隙介质力学的分析方法,依据应力应变数据计算了煤样孔隙度。研究发现,有效围压相同条件下的煤样孔隙度计算结果与渗透率实验结果的变化趋势一致;在三轴压缩实验条件下,煤样峰值强度前的渗透率降低幅度受有效围压的控制,有效围压越高,渗透率所历经的降低幅度越大。
Coupling effect of coal mass deformation and gas transfusion is an important issue in the research of gas outburst mechanism, and coal permeability is closely related to the stress state. To study the influence of effective confining pressure on coal permeability, the coal permeability experiment in whole stress -strain process was conducted under various gas pressures, the effect of gas pressure on coal strength and permeability was analyzed. Triaxial compression tests were conducted under a constant confining pressure （without methane）. According to porous media mechanics, coal porosities under different axial stresses were calculated based on coal stress and strain data of the triaxial compression tests. The results show that, the trends of coal porosity and permeability curves under the same effective confining pressure are roughly consistent; under triaxial compression, the effective confining pressure has an important effect on the permeability evolution before coal peak strength, higher effective confining pressure leads to shaper decrease in coal permeability before coal peak.
出处
《煤炭工程》
北大核心
2015年第5期87-90,共4页
Coal Engineering
基金
国家重点基础研究发展计划(973计划)资助项目(2010CB226801)
高等学校博士学科点专项科研基金资助课题(20120023120011)
中央高校基本科研业务费专项资金资助(2010QL02)
关键词
含瓦斯煤
渗透率
有效围压
孔隙度
coal containing methane
permeability
effective confining stress
porosity
