流体注入条件下煤层的扩容特性试验研究

陈嘉祺; 张东明; 邓博知

流体注入条件下煤层的扩容特性试验研究

计量
- 文章访问数: 29
- HTML全文浏览量: 0
- PDF下载量: 0
出版历程
- 发布日期: 2020-11-19

Experimental Study on Coal Seam Dilatancy Characteristics Under Fluid Injection

摘要

摘要: 为了更准确地认识流体注入导致煤体扩容的特征, 利用自主研发的煤岩热流固耦合试验系统开展了不同应力路径下的三轴加卸载试验。结果表明:原煤破坏失稳时,围压越大,其破坏时的体积应变越大,扩容性质越差。利用原煤的剪胀因子进行定量分析后发现,与恒定围压三轴压缩的应力路径相比,卸压和流体注入应力路径下原煤的扩容特性较好,但卸压和流体注入应力路径不能完全等效,原煤变形和扩容特性的存在差异,说明Biot系数的取值可能会随着岩石种类、应力状态发生较大幅度的变化,且流体进入煤岩后与煤体基质之间的毛细作用、吸附作用可能会造成原煤物理力学性质的变化。
- 煤层气 /
- 加卸载 /
- 流体注入 /
- 扩容 /
- 剪胀因子
Abstract: In order to more accurately understand the characteristics of coal volume expansion caused by fluid injection,a self-developed thermo-hydro-mechanical (THM) coupled with triaxial servo-controlled seepage apparatus for gas-infiltrated coal and rock was applied to carry out triaxial loading and unloading tests under different stress paths. The results show that when the raw coal is destabilized, the larger the confining pressure, the larger the volume strain at the time of its failure, and the worse the dilatancy capacity. It was found by quantitative analysis of the dilatancy factor of raw coal, compared with the stress path of triaxial compression with constant confining pressure, the dilatancy characteristics of raw coal under stress relief and fluid injection stress paths are better. The pressure relief and fluid injection stress paths cannot be completely equivalent, and there are differences in the deformation and dilatancy characteristics of the raw coal, this shows that the value of the Biot coefficient may vary greatly with the type of rock and stress state, and that capillary and adsorption between the fluid and the coal matrix after the fluid enters the coal rock may cause changes in the physical and mechanical properties of the raw coal.
- coalbed methane /
- loading and unloading /
- fluid injection /
- dilatancy /
- dilatancy factor

HTML全文

参考文献(16)

[1]	蔡美峰,何满潮,刘东燕.岩石力学与工程[M].北京:科学出版社,2002.
[2]	王凯,郑吉玉,朱奎胜.两种应力路径下无烟煤的变形破坏特征及能量分析[J].岩土力学,2015,36(S2):267-274.
[3]	李新元,陈培华,王吴一.极松软顶板工作面矿山压力活动规律[J].矿山压力与顶板管理,2004(4):4-7.
[4]	尹光志,蒋长宝,王维忠,等.不同卸围压速度对含瓦斯煤岩力学和瓦斯渗流特性影响试验研究[J].岩石力学与工程学报,2011,30(1):73-82.
[5]	汪斌,朱杰兵,邬爱清,等.锦屏大理岩加、卸载应力路径下力学性质试验研究[J].岩石力学与工程学报,2008,27(10):2138-2145.
[6]	张楚旋,戴兵,吴秋红.不同应力路径下岩石卸荷破坏过程的变形特性与能量耗散分析[J].中国安全生产科学技术,2014,10(10):35-40.
[7]	苏承东,高保彬,南华,等.不同应力路径下煤样变形破坏过程声发射特征的试验研究[J].岩石力学与工程学报,2009,28(4):757-766.
[8]	王在泉,张黎明,孙辉,等.不同卸荷速度条件下灰岩力学特性的实验研究[J].岩土力学,2011,32(4):1045-1050.
[9]	高春玉,徐进,何鹏,等.大理岩加、卸载力学特性的研究[J].岩石力学与工程学报,2005,24(3):456-460.
[10]	张凯,周辉,潘鹏志,等.不同卸荷速率下岩石强度特性研究[J].岩土力学,2010,31(7):2072-2078.
[11]	许江,李波波,周婷,等.加卸载条件下煤岩变形特性与渗透特征的试验研究[J].煤炭学报,2012,37(9):72-77.
[12]	吕有厂,秦虎.含瓦斯煤岩卸围压力学特性及能量耗散分析[J].煤炭学报,2012,37(9):1505-1510.
[13]	Yin G,Jiang C,Wang J G,et al. Combined effect of stress, pore pressure and temperature on methane permeability in anthracite coal: an experimental study[J]. Transport in porous media,2013,100(1): 1-16.
[14]	Yin G, Li M, Wang J G, et al. Mechanical behavior and permeability evolution of gas infiltrated coals during protective layer mining[J]. International Journal of Rock Mechanics and Mining Sciences, 2015, 80: 292.
[15]	Paterson M, Wong T. Experimental rock deformation-the brittle field[M]. Berlin: Springer Science & Business Media, 2005.
[16]	Wong T, David C, Zhu W. The transition from brittle faulting to cataclastic flow in porous sandstones: Mechanical deformation[J]. Journal of Geophysical Research: Solid Earth, 1997, 102(B2): 3009-3025.