Experimental study of the characteristics of strength and AE of Diorite porphyrite under complex loading and unloading path
FU Jianxin1，2，SONG Weidong1，2，TAN Yuye1，2
(1. School of Civil and Environmental Engineering，University of Science and Technology Beijing，Beijing 100083，China；2. State Key Laboratory of High-efficient Mining and Safety of Metal Mines，Ministry of Education，University of Science and Technology Beijing，Beijing 100083，China)
Abstract：Loading and unloading rock mechanics tests were tested using brittle rock from a typical deep mine. Mechanics and fracture characteristics of brittle rock under complex stress path were analysed. The AE ring count evolution characteristic in rupture process was studies using acoustic emission equipment. Studies have shown that，mechanical properties and deformation characteristics of rock have a close relationship with the confining pressure and its failure mode gradually transited from brittle fracture to ductile failure. Unloading operation amounted to apply a reverse rally on specimen surface that usually caused the rapid growth of radial displacement which named expansion phenomenon. Damage degree of unloading was more severe than loading and a large number of vertical cracks appear on rock surface so that rock damage form was composite tensile and compressive damage and acoustic emission count rate when the rock damaging of unloading was far greater than loading. The rock internal AE ring count evolution process was divided into three phases in the unloading process including calm before the peak period，active period and gentle period after peak. There were critical value of stress，strain and AE ring count in every period that got by a large number of laboratory tests and field monitoring.
付建新1，2，宋卫东1，2，谭玉叶1，2. 复杂加卸载路径下闪长玢岩强度特征及声发射特性试验研究[J]. 岩石力学与工程学报, 2016, 35(S2): 3858-3867.
FU Jianxin1，2，SONG Weidong1，2，TAN Yuye1，2. Experimental study of the characteristics of strength and AE of Diorite porphyrite under complex loading and unloading path. , 2016, 35(S2): 3858-3867.
吴玉山，李纪鼎. 大理岩卸载特性的研究[J]. 岩土力学，1984，5(1)：29-36.(WU Yushan，LI Jiding. Unloading properties of marble[J]. Rock and Soil Mechanics，1984，5(1)：29-36.(in Chinese))
[2]
PARK J W，RUTQVIST J，RYU D，et al. Coupled thermal-hydrological-mechanical behavior of rock mass surrounding a high-temperature thermal energy storage cavern at shallow depth[J]. International Journal of Rock Mechanics and Mining Sciences，2016，83：149-161.
[3]
PRIEST S. Three-dimensional failure criteria based on the Hoek-Brown criterion[J]. Rock Mechanics and Rock Engineering，2012，45：989-993.
[4]
ZHU Q. Strength prediction of dry and saturated brittle rocks by unilateral damage-friction coupling analysis[J]. Computers and Geotechnics，2016，73：16-23.
[5]
COOK M A，COOK U D，CLAY R B，et al. Behavior of rook during blasting[J]. Transaction of Social Mining Engineering，1966，10(2)：17-25.
[6]
BRADY H C，EDWIN T B. Rock mechanics for underground mining[M]. New York：Springer-Verlag，2002：522-527.
[7]
CAI M. Influence of stress path on tunnel excavation response-numerical tool selection and modeling strategy[J]. Tunnelling and Underground Space Technology，2008，23(6)：618-628.
[8]
SWANSON S R，BROWN W S. Anobservation of loading path independence of fracture rock[J].International Journal of Rock Mechanics and Mining Sciences andGeomechanics Abstracts，1971，8(3)：277-281.
[9]
尤明庆. 复杂路径下岩样的强度和变形特性[J]. 岩石力学与工程学报，2002，21(1)：23-28.(YOU Mingqing. Strength and deformation of rock specimen under complex loading path[J]. Chinese Journal of Rock Mechanics and Engineering，2002，21(1)：23-28.(in Chinese))
[10]
TAKAHASHI M，KOIDE H. Effect of the intermediate principal stress on strength and deformation behavior of sedimentary rocks at the depth shallower than 200m[C]// Proceedings of the ISRM-SPE International Symposium Rock at Great Depth. Pau，France：[s. n.]，1989：28-31.
[11]
TAHERI A，TANI K. Use of down-hole triaxial apparatus to estimate the mechanical properties of heterogeneous mudstone(CT) experiments on limestone damage evolution during unloading[J]. International Journal of Rock Mechanics and Mining Sciences，2008，45(8)：1390-1402.
[12]
胡 政，刘佑荣，武 尚，等. 高地应力区砂岩在卸荷条件下的变形参数劣化试验研究[J]. 岩土力学，2014，35(增1)：78-84.(HU Zheng，LIU Yourong，WU Shang，et al. Experimental study of deformation parameters degradation of sandstone in high geostress regions under unloading conditions[J]. Rock and Soil Mechanics，2014，35(Supp.1)：78-84.(in Chinese))
[13]
邓华锋，胡亚运，李建林，等. 考虑滞后效应的岩石加卸载响应比试验研究[J]. 岩石力学与工程学报，2015，34(增1) ：2915-2921.(DENG Huafeng，HU Yayun，LI Jianlin，et al. Experimental research on load/unload response ratio considering hysteresis effect of rock[J]. Chinese Journal of Rock Mechanics and Engineering，2015，34(Supp.1) ：2915-2921.(in Chinese))
2016, Vol. 35 
