|
|
|
| Experimental study on mechanical properties of bedding coal and rock under graded cyclic loading |
| LIU Zhongyu，DONG Xu，ZHANG Xuyang |
| (School of Civil Engineering，Zhengzhou University，Zhengzhou，Henan 450001，China) |
|
|
|
|
Abstract In order to study the deformation，failure and mechanical characteristics of bedding coal and rock under cyclic loading，parallel bedding and vertical bedding cylindrical coal samples were made，and uniaxial graded cyclic loading and unloading tests were carried out under different upper stress limits. Based on the test results，the residual deformation，elastic modulus and damage variables of the specimens during the cyclic loading process are analyzed. The results show that the elastic modulus of the two layered specimens varies with the number of cycles under low stress cycles. However，as the upper limit of stress increases，the fatigue damage in the specimen continues to accumulate，and the elastic modulus eventually shows a downward trend. At the same time，bedding coal and rock under cyclic loading have significant anisotropy characteristics. The specific manifestation is：for the sample with the loading direction perpendicular to the bedding，the damage variable increases sharply when the sample is locally damaged，showing brittle fracture，However，the damage variable of the specimen with the loading direction parallel to the layering showed a continuous growth trend before complete failure，showing obvious characteristics of plastic deformation.
|
|
|
|
|
|
[1] RUDAJEV V，VILHELM J，LOKAJICEK T. Laboratory studies of acoustic emission prior to uniaxial compressive rock failure[J]. International Journal of Rock Mechanics and Mining Sciences，2000，37(4)：699–704.
[2] 王恩元，何学秋，刘贞堂. 煤岩破裂声发射实验研究及RS统计分析[J]. 煤炭学报，1999，24(3)：48–51.(WANG Enyuan，HE Xueqiu，LIU Zhentang. Experimental research and R/S statistic analysis[J]. Journal of China Coal Society，1999，24(3)：48–51.(in Chinese))
[3] 吴 刚，赵震洋. 不同应力状态下岩石类材料破坏的声发射特性[J].岩土工程学报，1998，20(2)：82–85.(WU Gang，ZHAO Zhenyang. Acoustic emission character of rock materials failure during various stress states[J]. Chinese Journal of Geotechnical Engineering，1998，20(2)：82–85.(in Chinese))
[4] 艾 婷，张 茹，刘建锋，等. 三轴压缩煤岩破裂过程中声发射时空演化规律[J]. 煤炭学报，2011，36(12)：2 048–2 057.(AI Ting，ZHANG Ru，LIU Jianfeng，et al. Space-time evolution rules of acoustic emission locations under triaxial compression[J]. Journal of China Coal Society，2011，36(12)：2 048–2 057.(in Chinese))
[5] EBERHARDT E，STEAD D，STIMPSON B，et al. Identifying crack initiation and propagation thresholds in brittle rock[J]. Canadian Geotechnical Journal，1998，35(2)：222–233.
[6] EBERHARDT E，STEAD D，STIMPSON B. Quantifying progressive pre-peak brittle fracture damage in rock during uniaxial compression[J]. International Journal of Rock Mechanics and Mining Sciences，1999，36(3)：361–380.
[7] 葛修润，蒋 宇，卢允德，等. 周期荷载作用下岩石疲劳变形特性试验研究[J]. 岩石力学与工程学报，2003，22(10)：1 581–1 585.(GE Xiurun，JIANG Yu，LU Yunde，et al. Testing study on fatigue deformation law of rock under cyclic loading[J]. Chinese Journal of Rock Mechanics and Engineering，2003，22(10)：1 581–1 585.(in Chinese))
[8] 蒋 宇，葛修润，任建喜. 岩石疲劳破坏过程中的变形规律及声发射特性[J]. 岩石力学与工程学报，2004，23(11)：1 810–1 814. (JIANG Yu，GE Xiurun，REN Jianxi. Deformation rules and acoustic emission characteristics of rocks in process of fatigue failure[J]. Chinese Journal of Rock Mechanics and Engineering，2004，23(11)：1 810–1 814.(in Chinese))
[9] 周家文，杨兴国，符文熹，等. 脆性岩石单轴循环加卸载试验及断裂损伤特性力学研究[J]. 岩石力学与工程学报，2010，29(6)：1 172–1 183.(ZHOU Jiawen，YANG Xingguo，FU Wenxi，et al. Experimental test and fracture damage mechanical characteristics of brittle rock under uniaxial cyclic loading and unloading conditions[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(6)：1 172–1 183. (in Chinese))
[10] 杨小彬，韩心星，刘恩来，等. 单轴循环加卸载岩石非均匀变形演化特征[J]. 煤炭学报，2018，43(2)：449–456.(YANG Xiaobin，HAN Xinxing，LIU Enlai，et al. Properties of non-uniform deformation evolution of rock under uniaxial cyclic loading and unloading[J]. Journal of China Coal Society，2018，43(2)：449–456. (in Chinese))
[11] 杨小彬，韩心星，刘恩来，等. 循环加卸载下花岗岩非均匀变形演化的声发射特征试验研究[J]. 岩土力学，2018，39(8)：2 732–2 739. (YANG Xiaobin，HAN Xinxing，LIU Enlai，et al. Experimental study on the acoustic emission characteristics of non-uniform deformation evolution of granite under cyclic loading and unloading test[J]. Rock and Soil Mechanics，2018，39(8)：2 732–2 739.(in Chinese))
[12] 杨永杰，宋 扬，楚 俊. 循环荷载作用下煤岩强度及变形特征试验研究[J]. 岩石力学与工程学报，2007，26(1)：201–205.(YANG Yongjie，SONG Yang，CHU Jun. Experimental study on characteristics of strength and deformation of coal under cyclic loading[J]. Chinese Journal of Rock Mechanics and Engineering，2007，26(1)：201–205. (in Chinese))
[13] 李晓泉，尹光志，蔡 波. 循环载荷下突出煤样的变形和渗透特性试验研究[J]. 岩石力学与工程学报，2010，29(增2)：3 498–3 504. (LI Xiaoquan，YIN Guangzhi，CAI Bo. Experimental study on deformation and seepage properties of outburst coal samples under cyclic loading[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(Supp.2)：3 498–3 504.(in Chinese))
[14] 邹俊鹏，陈卫忠，杨典森，等. 循环荷载条件下原煤力学性质及损伤演化规律[J]. 煤炭学报，2016，41(7)：1 675–1 682.(ZOU Junpeng，CHEN Weizhong，YANG Diansen，et al. Mechanical properties and damage evolution of coal under cyclic loading conditions[J]. Journal of China Coal Society，2016，41(7)：1 675–1 682. (in Chinese))
[15] 张晖辉，颜玉定，余怀忠，等. 循环载荷下大试件岩石破坏声发射实验——岩石破坏前兆的研究[J]. 岩石力学与工程学报，2004，23(21)：3 621–3 628.(ZHANG Huihui，YAN Yuding，YU Huaizhong，et al. Acoustic emission experimental research onlarge-scaled rock failure under cycling load——fracture precursor of rock[J]. Chinese Journal of Rock Mechanics and Engineering，2004，23(21)：3 621–3 628.(in Chinese))
[16] YU H Z，YIN X C，XIA M F，et al. Experimental research on critical point hypothesis[J]. Acta Seismologica Sinica，2004，17(1)：129–137.
[17] 李晓泉，尹光志，蒋长宝，等. 阶段性循环载荷对突出煤样渗透特性的影响[J]. 重庆大学学报，2012，35(1)：110–116.(LI Xiaoquan，YIN Guangzhi，JIANG Changbao，et al. Effect of ourburst coal?s gas seepage properties under stage cyclic loading[J]. Journal of Chongqing University，2012，35(1)：110–116.(in Chinese))
[18] 宋 远，李化敏，刘 闯. 不同层理方向煤岩单轴压缩声发射特征试验[J]. 煤矿安全，2018，49(11)：39–43.(SONG Yuan，LI Huamin，LIU Chuang. Experimental research on acoustic emission characteristics of coal rock with different bedding directions under uniaxial compression[J]. Safety in Coal Mines，2018，49(11)：39–43.(in Chinese))
[19] 周志华，曹 平，叶洲元，等. 单轴循环载荷与渗透水压下预应力裂隙岩石破坏试验研究[J]. 采矿与安全工程学报，2014，31(2)：292–298.(ZHOU Zhihua，CAO Ping，YE Zhouyuan，et al. Failure characteristics of prestress fractured rock under uniaxial cyclic loading and seepage water pressure[J]. Journal of Mining and Safety Engineering，2014，31(2)：292–298.(in Chinese))
[20] 尤明庆，苏承东. 大理岩试样循环加载强化作用的试验研究[J]. 固体力学学报，2008，29(1)：66–72.(YOU Mingqing，SU Chengdong. Experimental study on strengthening of marble specimen in cyclic loading of uniaxial or pseudo-triaxial compression[J]. Chinese Journal of Solid Mechanics，2008，29(1)：66–72. (in Chinese))
[21] 徐速超，冯夏庭，陈炳瑞. 矽卡岩单轴循环加卸载试验及声发射特性研究[J]. 岩土力学，2009，30(10)：2 929–2 934.(XU Suchao，FENG Xiating，CHEN Bingrui. Experimental study of skarn under uniaxial cyclic loading and unloading test and acoustic emission characteristics[J]. Rock and Soil Mechanics，2009，30(10)：2 929–2 934.(in Chinese))
[22] 陈运平，王思敬，王恩志. 循环荷载下层理岩石的弹性和衰减各向异性[J]. 岩石力学与工程学报，2006，25(11)：2 233–2 239.(CHEN Yunping，WANG Sijing，WANG Enzhi. Elastic and attenuative of bedding rock under cyclic loading[J]. Chinese Journal of Rock Mechanics and Engineering，2006，25(11)：2 233–2 239.(in Chinese))
[23] 谢和平，鞠 杨，董毓利. 经典损伤定义中的“弹性模量法”探讨[J].力学与实践，1997，19(2)：1–5.(XIE Heping，JU Yang，DONG Minli. Discussion about“elastic modulus method”in the classic definition of damage[J]. Mechanics and Practice，1997，19(2)：1–5.(in Chinese))
|
|
|
|
2021, Vol. 40 
