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| INVESTIGATION ON FAILURE BEHAVIOR OF BASALT FROM DIFFERENT DEPTHS BASED ON THREE-POINT BENDING MESO-EXPERIMENTS |
| ZUO Jianping1，2，CHAI Nengbin2，ZHOU Hongwei1，2 |
| (1. State Key Laboratory of Coal Resources and Safe Mining，China University of Mining and Technology，Beijing 100083，China；2. School of Mechanics and Civil Engineering，China University of Mining and Technology，Beijing 100083，China) |
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Abstract Most of deep rock mechanics focus on rock samples from the same depth in the existing literatures. People hope to investigate the effects of different depths on mechanical behavior through applying different confining pressures on samples. In addition，the physico-mechanical behaviors of different depth rocks have been reported in many literatures. However，it is well known that both the confining pressure and rock microstructure will change with the increasing depth. In Mentougou district in Beijing，there is a special area，where from the surface to the depth of 1 100 meters，there is basically a same lithology，namely basalt. Scanning electron microscope(SEM) system with loading devices has been successfully employed to investigate the mesoscopic failure behavior of Mengtougou basalt with centric preset notch in different depths，offsetting single notch and double notches basalt. We hope to reveal mesoscopic mechanism of basalts with changing depths. Experimental results indicate that the crack will initiate from preset notch and develop into a continuous main crack for most of basalt samples in three-point bending tests. Both the failure load and the fracture energy for different depth basalts increase with the depth. The main reasons are that not only the microstructure of deep basalt is compact，but the porosity is smaller with the increasing depth. Both peak load and fracture energy of basalt with single preset notch are approximately same with those of double preset notches for the same offsetting distance. In addition，peak load and fracture energy will linearly increase with the increasing offsetting distance. The main reason is that though the failure of basalts with offsetting notch is affected by both of shear force and bending moment；and the bending moment gradually decreases with the increasing offsetting distance which induce the increase of peak load and fracture energy increase.
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Received: 30 October 2012
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| [1] 谢和平. 深部高应力下的资源开采——现状、基础科学问题与展望[C]// 175次香山科学会议. 北京：中国环境科学出版社，2002：179–191.(XIE Heping. Resources development under high ground stress：present state，basic science problems and perspective[C]// Proceedings of the 175th Xiangshan Science Congress. Beijing：China Environmental Science Press，2002：179–191.(in Chinese))
[2] 周宏伟，谢和平，左建平. 深部高地应力下岩石力学行为研究进展[J]. 力学进展，2005，35(1)：91–99.(ZHOU Hongwei，XIE Heping，ZUO Jianping. Developments in researches on mechanical behaviors of rocks under the condition of high ground pressure in the depths[J]. Advances in Mechanics，2005，35(1)：91–99.(in Chinese))
[3] 周维垣. 高等岩石力学[M]. 北京：水利水电出版社，1990：3–6. (ZHOU Weiyuan. Advanced rock mechanics[M]. Beijing：Water Resources and Hydropower Press，1990：3–6.(in Chinese))
[4] PATERSON M S. Experimental deformation and faulting in Wombeyan marble[J]. Geological Society of America Bulletin，1958，69(4)：465–467.
[5] KWASNIEWSKI M. Laws of brittle failure and of B-D transition in sandstone[C]// MAURY V，FOURMAINTRAX D ed. Rock at Great Depth. Rotterdam：A. A. Balkema，1989：45–58.
[6] TUGRUL A，ZARIF I H. Correlation of mineralogical and textural characteristics with engineering properties of selected granitic rocks from Turkey[J] . Engineering Geology，1999，51(4)：303–317.
[7] 王明洋，戚承志，钱七虎. 深部岩体块系介质变形与运动特性研究[J]. 岩石力学与工程学报，2005，24(16)：2 825–2 830.(WANG Mingyang，QI Chengzhi，QIAN Qihu. Study on deformation and motion characteristics of blocks in deep rock mass[J]. Chinese Journal of Rock Mechanics and Engineering，2005，24(16)：2 825–2 830.(in Chinese))
[8] 周小平，钱七虎，杨海清. 深部岩体强度准则[J]. 岩石力学与工程学报，2008，27(1)：117–123.(ZHOU Xiaoping，QIAN Qihu，YANG Haiqing. Strength criteria of deep rock mass[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(1)：117–123.(in Chinese))
[9] 冯夏庭，江 权，苏国韶. 高应力下硬岩地下工程的稳定性智能分析与动态优化[J]. 岩石力学与工程学报，2008，27(7)：1 341–1 352. (FENG Xiating，JIANG Quan，SU Guoshao. Integrated intelligent stability analysis and dynamic optimization of underground engineering in hard rock with high geostress[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(7)：1 341–1 352.(in Chinese))
[10] 周宏伟，谢和平，左建平，等. 赋存深度对岩石力学参数影响的实验研究[J]. 科学通报，2010，55(34)：3 276–3 284.(ZHOU Hongwei，XIE Heping，ZUO Jianping，et al. Experimental study of the effect of
depth on mechanical parameters of rock[J]. Chinese Science Bulletin，2010，55(34)：3 276–3 284.(in Chinese))
[11] 左建平，柴能斌，周宏伟. 赋存深度对玄武岩变形破坏及能量特征的影响研究[J]. 地下空间与工程学报，2011，7(6)：1 175–1 180. (ZUO Jianping，CHAI Nengbin，ZHOU Hongwei. Study on the effect of buried depth on failure and energy characteristics of the basalt[J]. Chinese Journal of Underground Space and Engineering，2011，7(6)：1 175–1 180.(in Chinese))
[12] 左建平，周宏伟，谢和平，等. 温度和应力耦合作用下砂岩破坏的细观试验研究[J]. 岩土力学，2008，29(6)：1 477–1 482.(ZUO Jianping，ZHOU Hongwei，XIE Heping，et al. Meso-experimental research on sandstone failure behavior under thermal-mechanical coupling effect[J]. Rock and Soil Mechanics，2008，29(6)：1 477–1 482. (in Chinese))
[13] 彭瑞东，武志德，周宏伟，等. 层状盐岩中裂纹扩展规律的细观实验研究[J]. 岩石力学与工程学报，2011，30(增2)：3 953–3 959. (PENG Ruidong，WU Zhide，ZHOU Hongwei，et al. Meso-experimental investigation on crack evolution in bedded salt rock[J]. Chinese Journal of Rock Mechanics and Engineering，2011，30(Supp.2)：3 953–3 959. (in Chinese))
[14] 左建平，周宏伟，方 园，等. 甘肃北山地区深部花岗岩的热开裂试验研究[J]. 岩石力学与工程学报，2011，30(6)：1 107–1 115. (ZUO Jianping，ZHOU Hongwei，FANG Yuan，et al. Experimental research on thermal cracking of deep granite in Beishan region，Gansu province[J]. Chinese Journal of Rock Mechanics and Engineering，2011，30(6)：1 107–1 115.(in Chinese))
[15] 中国航空研究院. 应力强度因子手册[M]. 北京：科学出版社，1981：188–189.(Chinese Institute of Aeronautics. Handbook of stress intensity factors[M]. Beijing：Science Press，1981：188–189.(in Chinese))
[16] 孙训方. 材料力学[M]. 4版. 北京：高等教育出版社，2008：137–138.(SUN Xunfang. Material mechanics[M]. 4th ed. Beijing：Higher Education Press，2008：137–138.(in Chinese))
[17] 蔡美峰，王金安，王双红. 玲珑金矿深部开采岩体能量分析与岩爆综合预测[J]. 岩石力学与工程学报，2001，20(1)：38–42.(CAI Meifeng，WANG Jin?an，WANG Shuanghong. Analysis of energy distribution and prediction of rock burst during deep mining excavation in Linglong gold mine[J]. Chinese Journal of Rock Mechanics and Engineering，2001，20(1)：38–42.(in Chinese)) |
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2013, Vol. 32 
