高应力下原煤三轴卸荷力学特性研究

doi:10.13722/j.cnki.jrme.2014.s2.006

摘要
图/表
参考文献(15)
相关文章 (15)

全文: PDF (2744 KB) HTML (1 KB)
输出: BibTeX | EndNote (RIS)

摘要基于取自淮南矿区－780 m标高B10煤层的原煤，进行高应力下不等量卸围压和轴压的原煤卸荷试验，并与同围压下的常规三轴试验结果进行对比分析，研究卸荷条件下原煤的变形、强度、参数及破坏特征。研究结果表明：(1) 从卸荷点起，偏应力–轴向应变曲线即突变“上仰”，斜率升高；但与常三轴曲线相比，卸荷峰值轴向应变显然减小，屈服进程明显缩短，峰后脆性破坏特征显著。(2) 偏应力–侧向应变曲线从卸荷点开始突变“下跌”，斜率降低，峰值侧向应变明显小于常三轴；且峰后破坏前应力跌落较慢，3变化较大，而常三轴则跌落迅速，3变化较小。(3) 偏应力–体积应变曲线从卸荷点起即反转左拐，呈现明显扩容，且在峰值点附近扩容最为剧烈。而常三轴曲线则除在较低围压下表现出扩容特征外，高围压下始终向右延展，呈现不断收缩状态。(4) 卸荷时变形模量E始终降低，而损伤因子D和泊松比则一直增大；且三者变化趋势均在峰前平缓，峰后逐渐加剧。随初始围压的增加，E，D，总体上均呈升高趋势。(5) 卸荷煤样以剪切破坏为主，破断角θ = 20°～32°，且随初始围压的增加，θ以抛物线趋势升高；初始围压相同时，角度小于常三轴。(6) 卸荷条件下煤岩抗剪强度参数c值明显小于常三轴，而值则变化不大。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	刘泉声1
	刘恺德1
	2
	卢兴利1
	朱杰兵3

关键词 ：岩石力学, 高应力, 原煤, 卸荷, 变形特征, 强度特征, 破坏机制, 力学参数

Abstract：Based on the raw coal from B10 seam of －780 m in Huainan coal mine，unloading tests under high stress were carried out in the style of non-uniform velocity of unloading confining pressure and axial pressure synchronously，and the test results were compared with that of conventional triaxial experiments under the same confining pressure. The deformation，strength，parameters and failure characteristics of the raw coal under unloading were studied. The results show that：(1) From the unloading point，the deviatoric stress-axial strain curves pitch up abruptly，and its gradient increases. But compared with conventional triaxial curve，peak axial strain under unloading condition decreases apparently，yield process is obviously shorten and post-peak brittle failure characteristics is significant. (2) From the unloading point，the deviatoric stress - lateral strain curves fall abruptly，and its gradient decreases. The peak lateral strain is smaller than that of conventional triaxial curves. Before post-peak destroying，the stress drops slowly，and 3 changes greatly. While that of conventional triaxial curves fall rapidly，and 3 changes small. (3) From unloading point，the deviatoric stress-volume strain curves reverse left instantly，presenting the features of obvious dilatancy. And in the interval near peak point，the dilatancy is the strongest. However，except the conventional triaxial curves show dilatancy characteristics under low confining pressure conditions，the curves always extended right under high confining pressure，and presenting a continuous shrinkage state. (4) In the process of unloading，the deformation modulus E always reduces，and the damage factor D and Poissons ratio μ always increase. And the three change trend are gentle before peak，gradually increase after peak. Moreover，the E，D and μ all increase in general with the increase of initial confining pressure. (5) The failure modes of unloading coal samples are mainly shear failure，and rupture angle is in the range of 20°–32°，which increases in parabolic trend with the increase of confining pressure. Under the same initial confining pressure，the value of θ is less than that of the triaxial angle. (6) The shear strength parameters c of coal under unloading is less than that of the triaxial，and the value of is very close.

Key words： rock mechanics high stress raw coal unloading deformation feature strength characteristic failure mechanism mechanical parameters

引用本文:

刘泉声1，刘恺德1，2，卢兴利1，朱杰兵3. 高应力下原煤三轴卸荷力学特性研究[J]. 岩石力学与工程学报, 2014, 33(S2): 3429-3438.
LIU Quansheng1，LIU Kaide1，2，LU Xingli1，ZHU Jiebing3. STUDY OF MECHANICAL PROPERTIES OF RAW COAL UNDER HIGH STRESS WITH TRIAXIAL UNLOADING. , 2014, 33(S2): 3429-3438.

链接本文:

https://rockmech.whrsm.ac.cn/CN/10.13722/j.cnki.jrme.2014.s2.006 或 https://rockmech.whrsm.ac.cn/CN/Y2014/V33/IS2/3429

[1] 刘泉声，刘恺德，朱杰兵，等. 高应力下原煤三轴压缩力学特性研究[J]. 岩石力学与工程学报，2014，33(1)：24–34.(LIU Quansheng，LIU Kaide，ZHU Jiebing，et al. Study of mechanical properties of raw coal under high stress with triaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(1)：24–34.(in Chinese))

[2] 袁亮. 低透气性煤层群无煤柱煤气共采理论与实践[J]. 中国工程科学，2009，11(5)：72–80.(YUAN Liang. Theory and practice of integrated pillarless coal production and methane extraction in multiseams of low permeability[J]. Engineering Sciences，2009，11(5)：72–80.(in Chinese))

[3] 黄润秋，黄达. 卸荷条件下花岗岩力学特性试验研究[J]. 岩石力学与工程学报，2008，27(11)：2 205–2 213.(HUANG Runqiu，HUANG Da. Experimental research on mechanical properties of granites under unloading condition[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(11)：2 205–2 213.(in Chinese))

[4] 张成良，赵晓霞. 辉绿岩在加、卸荷条件下的岩体力学特性试验[J]. 煤炭学报，2011，36(增2)：224–230.(ZHANG Chengliang，ZHAO Xiaoxia. Experiment on mechanics properties of diabase under the press of loading and unloading[J]. Journal of China Coal Society，2011，36(Supp.2)：224–230.(in Chinese))

[5] 刘恺德，刘泉声，朱元广，等. 考虑层理方向效应煤岩劈裂及单轴压缩试验研究[J]. 岩石力学与工程学报，2013，32(2)：1–9.(LIU Kaide，LIU Quansheng，ZHU Yuanguang，et al. Experimental study of coal considering directivity effect of bedding plane under Brazilian splitting and uniaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering，2013，32(2)：1–9.(in Chinese))

[6] 王贤能，黄润秋. 岩石卸荷破坏特征与岩爆效应[J]. 山地研究，1998，16(4)：26–30.(WANG Xianneng，HUANG Runqiu. Analysis of deformation and failure features characteristics of rock under unloalding conditions and their effects on rock burst[J]. Mountain Research，1998，16(4)：26–30.(in Chinese))

[7] 谢红强，何江达，徐进. 岩石加卸载变形特性及力学参数试验研究[J]. 岩土工程学报，2003，25(3)：336–338.(XIE Hongqiang，HE Jiangda，XU Jin. Deformation characteristics of rock under loading and unloading conditions and experimental study of mechanical parameters[J]. Chinese Journal of Geotechnical Engineering，2003，25(3)：336–338.(in Chinese))

[8] 李宏哲，夏才初，闫子舰，等. 锦屏水电站大理岩在高应力条件下的卸荷力学特性研究[J]. 岩石力学与工程学报，2007，26(10)：2 104–2 109.(LI Hongzhe，XIA Caichu，YAN Zijian，et al. Study on marble unloading mechanical properties of Jinping hydropower station under high geostress conditions. Chinese Journal of Rock Mechanics and Engineering，2007，26(10)：2 104–2 109.(in Chinese))

[9] 黄润秋，黄达. 高地应力条件下卸荷速率对锦屏大理岩力学特性影响规律试验研究[J]. 岩石力学与工程学报，2010，29(1)：21–33.(HUANG Runqiu，HUANG Da. Experimental research on affection laws of unloading rates on mechanical properties of Jinping marble under high geostress[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(1)：21–33.(in Chinese))

[10] 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.(GAO Chunyu，XU Jin，HE Peng，et al. Study on mechanical properties of marble under loading and unloading conditions[J]. Chinese Journal of Rock Mechanics and Engineering，2005，24(3)：456–460.(in Chinese))

[11] J勒迈特. 损伤力学教程[M]. 陶春虎译. 北京：科学出版社，1996：13–26.(LEMAITRE J. A course on damage mechanics[M]. Translated by Tao Chunhu. Beijing：Science Press，1996：13–26.(in Chinese))

[12] 朱杰兵. 高应力下岩石卸荷及其流变特性研究[博士学位论文][D]. 武汉：中国科学院武汉岩土力学研究所，2009.(ZHU Jiebing. Study on unloading mechanics and its rheological properties of rock under high tress[Ph. D. Thesis][D]. Wuhan：Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，2009.(in Chinese))

[13] 吕颖慧，刘泉声，江浩. 基于高应力下花岗岩卸荷试验的力学变形特性研究[J]. 岩土力学，2010，31(2)：337–344.(LU Yinghui，LIU Quansheng，JIANG Hao. Study of mechanical deformation characteristics of granite in unloading experiments of high stress[J]. Rock and Soil Mechanics，2010，31(2)：337–344.(in Chinese))

[14] 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)：2 138–2 145.(WANG Bin，ZHU Jiebing，WU Aiqing，et al. Experimental study on mechanical properties of Jinping marble under loading and unloading stress paths[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(10)：2 138–2 145.(in Chinese))

[15] 吕颖慧，刘泉声，胡云华. 基于花岗岩卸荷试验的损伤变形特征及其强度准则[J]. 岩石力学与工程学报，2009，28(10)：2 096– 2 103.(LU Yinghui，LIU Quansheng，HU Yunhua. Damage deformation characteristics and its strength criterion based on unloading experiments of granites[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(10)：2 096–2 103.(in Chinese))