轴向加载速率对原煤力学和渗透特性的影响
Effect of axial loading rate on mechanical and permeability properties of raw coal
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摘要: 采用煤岩流变仪对原煤进行了不同轴向加载速率下的常规三轴力学渗流试验，运用体积扩容应力、峰值应力、弹性模量和变形模量作为原煤的力学指标，发现试验所用原煤与典型的脆性岩石的规律相同，原煤作为非线性弹性材料体，4种力学指标均随着轴向加载速率的增大而增大；加载过程煤样能量耗散可分为峰前和峰后阶段，峰前阶段绝大部分吸收的能量转化为可释放弹性应变能，耗散应变能增加的速率较缓，峰后阶段弹性应变能急剧下降，大量释放并转化为耗散应变能；同时应力峰值处的总能量随轴向加载速率的增大而增大；渗透率-应变曲线总体呈现“V”字形的变化特征；在全应力-应变过程中，煤岩渗透率与轴向应变之间满足二次多项式函数关系。Abstract: The coal-rock rheometer was used to carry out conventional triaxial mechanical seepage experiments on raw coal under different axial loading rates in this paper. Volume expansion stress, peak stress, elastic modulus and deformation modulus were used as mechanical indexes of raw coal. It was found that the law of raw coal used in the experiment was the same as that of typical brittle rock. The mechanical properties increase with the increase of axial loading rate. During the loading process, the energy dissipation of coal samples can be divided into pre-peak stage and post peak stage. Most of the energy absorbed in the pre-peak stage is transformed into releasable elastic strain energy, and the rate of dissipative strain energy increasing is relatively slow. In the post peak stage, the elastic strain energy decreases sharply and a large amount is released and converted into dissipative strain energy. At the same time, the total energy at the peak stress increases with the increase of axial loading rate. The permeability strain curve generally presents a “V” shape. In the whole stress-strain process, the relationship between coal permeability and axial strain satisfies quadratic polynomial function.
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Keywords:
- raw coal /
- loading rate /
- peak stress /
- energy dissipation /
- permeability /
- mechanical properties of coal and rock
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[1] 尹小涛，葛修润，李春光，等．加载速率对岩石材料力学行为的影响[J]．岩石力学与工程学报，2010，29（Ｓ1）：2610－2615. YIN Xiaotao, GE Xiurun, LI Chunguang, et al. Influences of loading rates on mechanical behaviors of rock materials[J]. Chinese Journal of Rock Mechanics and Engineering, 2010, 29（S1）: 2601-2615.
[2] Yamamuro J A. Effects of strain rate on instability of granular soils[J]. Geotech Test J., 1993, 16（3）:10. [3] 李彦伟，姜耀东，杨英明，等．煤单轴抗压强度特性的加载速率效应研究[J]．采矿与安全工程学报，2016， 33（4）：754－760. LI Yanwei, JIANG Yaodong, YANG Yingming, et al. Research on loading rate effect of uniaxial compressive strength of coal[J]. Journal of Mining and Safety Engineering, 2016, 33（4）: 754-760.
[4] LIANG WG, ZHAO Y S, XU SG, et al. Effect of strain rate on the mechanical properties of salt rock[J]. International Journal of Rock Mechanics and Mining Sciences, 2011, 48（1）: 161-167. [5] 陈飞，李顺才，喻秋，等．不同加载速率下小纪汗煤矿煤样强度及声发射特征研究[J]．煤矿安全，2019，50（1）：48-51. CHEN Fei, LI Shuncai, YU Qiu, et al. Strength and acoustic emission characteristics under different loading rates for coal samples from Xiaojihan Coal Mine[J]. Safety in Coal Mines 2019, 50（1）: 48-51.
[6] Backers T, Fardin N, Dresen G, et al. Effect of loading rate on Mode I fracture toughness, roughness and micromechanics of sandstone[J]. International Journal of Rock Mechanics and Mining Sciences, 2003, 40（3）: 425-433. [7] 安美秀．不同加载速率含水煤层渗透性及声发射实验研究[D]．太原：太原理工大学，2017. [8] 尹光志，何兵，王浩，等．深部采动影响下覆岩蠕变损伤破坏规律[J]．煤炭学报，2015，40（6）：1390－1395. YIN Guangzhi, HE Bing, WANG Hao, et al． Damage law of overlying rock induced by mining[J]． Journal of China Coal Society, 2015, 40（6）: 1390-1395.
[9] 黄达，黄润秋，张永兴．粗晶大理岩单轴压缩力学特性的静态加载速率效应及能量机制试验研究[J]．岩石力学与工程学报，2012，31（2）：245－255. HUANG Da, HUANG Runqiu, ZHANG Yongxing. Experimental investigations on static loading rate effects on mechanical properties and energy mechanism of coarse crystal grain marble under uniaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering, 2012, 31（2）: 245-255.
[10] 杨仕教，曾晟，王和龙．加载速率对石灰岩力学效应的试验研究[J]．岩土工程学报，2005，27（7）：786. YANG Shijiao, ZENG Sheng, WANG Helong. Experimental analysis on mechanical effects of loading rates on limestone[J]. China Civil Engineering Journal, 2005, 27（7）: 786.
[11] 苏海健，靖洪文，赵洪辉．高温后砂岩单轴压缩加载速率效应的试验研究[J]．岩土工程学报，2014，36（6）：1064－1071. SU Haijian, JIN Hongwen, ZHAO Honghui. Experimental investigation on loading rate effect of sandstone after high temperature under uniaxial compression[J]. China Civil Engineering Journal, 2014, 36（6）: 1064.
[12] 蒋长宝，魏财，段敏克，等．饱水和天然状态下页岩滞后效应及阻尼特性研究[J]．岩土力学，2020，41（6）：1－10. JIANG Changbao, WEI Cai, DUAN Minke, et al. Hysteresis effect and damping characteristics of shale under saturated and natural state[J]. Rock and Soil Mechanics, 2020, 41（6）: 1-10.
[13] DUAN Minke, JIANG Changbao, XING Huilin, et al. Study on damage of coal based on permeability and load-unload response ratio under tiered cyclic loading[J]. Arabian Journal of Geosciences, 2020, 13: 6. [14] 段敏克．采动影响下固－液－气耦合机理及瓦斯运移规律研究[D]．重庆：重庆大学，2017. [15] 蒋长宝，段敏克，尹光志，等．不同含水状态下含瓦斯原煤加卸载试验研究[J]．煤炭学报，2016，41（9）：2230-2237. JIANG Changbao, DUAN Minke, YIN Guangzhi, et al． Loading-unloading experiments of coal containing gas under the condition of different moisture contents[J]. Journal of China Coal Society, 2016, 41（9）: 2230.
[16] 许国安，牛双建，靖洪文，等．砂岩加卸载条件下能耗特征试验研究[J]．岩土力学，2011，32（12）：3611. XU Guoan, NIU Shuangjian, JING Hongwen, et al． Experimental study of energy features of sandstone under loading and unloading[J]. Rock and Soil Mechanics, 2011, 32（12）: 3611.
[17] 段敏克，蒋长宝，俞欢，等．分级加－卸载条件下原煤渗透及能耗特征研究[J]．岩土力学，2018，39（4）：1346－1354. DUAN Minke, JIANG Changbao, YU Huan, et al. Study on permeability and energy consumption characteristics of raw coal under graded loading-unloading conditions[J]. Rock and Soil Mechanics, 2018, 39（4）: 1346-1354.
[18] JIANG Changbao, DUAN Minke, YIN Guangzhi, et al. Experimental study on seepage properties, AE characteristics and energy dissipation of coal under tiered cyclic loading[J]. Engineering Geology, 2017, 211: 114-123. [19] DUAN Minke, JIANG Changbao, GAN Quan, et al. Study on permeability anisotropy of bedded coal under true triaxial stress and its application[J]. Transport in Porous Media, 2020, 131: 1007-1035. [20] 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）：1493－1498. XU Jiang, LI Bobo, ZHOU Ting, et al. Experimental study of coal deformation and permeability characteristics under loading-unloading conditions[J]. Journal of China Coal Society, 2012, 37（9）: 1493-1498．
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