Mechanical properties and acoustic emission characteristics of coal samples with a single natural joint of different dip angles

Bulletin of Engineering Geology and the Environment - 2023
Feng Ju1,2, Dong Wang1,2, Zhongwei Wang3, Meng Xiao1,2, Zequan He1,2, Pai Ning1,2, Tengfei Wang1,2, Li Li1, Chaoseng Yan1, Tao Zhou1
1School of Mechanics and Civil Engineering, China University of Mining and Technology, Xuzhou, China
2State Key Laboratory for Geomechanics and Deep Underground Engineering (China University of Mining and Technology), Xuzhou, China
3China Coal Technology and Engineering Group, Taiyuan Research Institute, Taiyuan, China

Tóm tắt

The existence of joints reduces the strength of coal and increases the failure probability of coal pillars. To predict and prevent coal pillar failure, it is necessary to clarify the influence of joint dip angle β on coal strength. In this paper, acoustic emission (AE) and unconstrained compression experiments were carried out on coal samples containing a single natural joint with different dip angles. It is found that the mechanical properties and AE characteristics of jointed samples have obvious anisotropy: (1) as β increased, the peak strength, crack initiation stress, peak strain, crack damage stress, Young’s modulus, and crack closure stress of samples decreased first and then increased, while the residual strength displayed a monotonic decrease. (2) As β increased, the failure mode of the samples changed from splitting to shear, and then back to splitting. (3) The closer the β was to 60°, the lower the sample’s strength was, the more active the AE events were, and the sample was more prone to slide along the joint surface. The findings indicate that coal pillars with a joint dip angle close to 60° are most likely to experience shear failure and instability, and that reinforcement measures should be taken in advance to ensure the safety of mining production.

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Tài liệu tham khảo

An X, Ning Y, Ma G, He L (2014) Modeling progressive failures in rock slopes with non-persistent joints using the numerical manifold method. Int J Numer Anal Methods Geomech 38:679–701

Chen X, Liao Z, Peng X (2012) Deformability characteristics of jointed rock masses under uniaxial compression. Int J Min Sci Technol 22:213–221

Chen Z, Xu L, Shang Y (2021) Influence of joint angle on the acoustic emission evolution characteristics and energy dissipation rule of rock mass. Geotech Geol Eng 39:1621–1635

Chen PW, Huang T, Yang J, Zhang GX (2006) Numerical simulation of rock fracture under dynamic loading using manifold method. Key Eng Mater 324–325:235–238. https://doi.org/10.4028/www.scientific.net/KEM.324-325.235

Chen Y, Lu A, Mao X et al (2017) Nonlinear dynamics mechanism of rock burst induced by the instability of the layer-crack plate structure in the coal wall in deep coal mining. Shock Vib 2017:1–12. https://doi.org/10.1155/2017/4051967

Das AJ, Mandal PK, Bhattacharjee R et al (2017) Evaluation of stability of underground workings for exploitation of an inclined coal seam by the ubiquitous joint model. Int J Rock Mech Min Sci 93:101–114

Eberhardt E, Stead D, Stimpson B, Read RS (1998) Identifying crack initiation and propagation thresholds in brittle rock. Can Geotech J 35:222–233. https://doi.org/10.1139/t97-091

Fairhurst C, Hudson JA (1999) Draft ISRM suggested method for the complete stress-strain curve for intact rock in uniaxial compression. Int J Rock Mech Min Sci 1997 36:279–289

Fan X, Yu H, Deng Z et al (2022) Cracking and deformation of cuboidal sandstone with a single nonpenetrating flaw under uniaxial compression. Theor Appl Fract Mech 119:103284

Fu J-W, Chen K, Zhu W et al (2016) Progressive failure of new modelling material with a single internal crack under biaxial compression and the 3-D numerical simulation. Eng Fract Mech 165:140–152

Guo S, Qi S, Zou Y, Zheng B (2017) Numerical studies on the failure process of heterogeneous brittle rocks or rock-like materials under uniaxial compression. Materials 10:378

Huang C, Yang W, Duan K et al (2019) Mechanical behaviors of the brittle rock-like specimens with multi-non-persistent joints under uniaxial compression. Constr Build Mater 220:426–443

Hui X, Ma F, Xu J, Guo J (2017) Study on statistical damage constitutive model for rocks considering length and occurrence distribution of joint fissures. Chin J Rock Mech Eng 36:3233–3238

Iskander M, Shrive N (2018) Fracture of brittle and quasi-brittle materials in compression: a review of the current state of knowledge and a different approach. Theor Appl Fract Mech 97:250–257. https://doi.org/10.1016/j.tafmec.2018.08.014

Ju Y, Sun H, Xing M et al (2018) Numerical analysis of the failure process of soil–rock mixtures through computed tomography and PFC3D models. Int J Coal Sci Technol 5:126–141

Kaiser J (1950) An investigation into the occurrence of noises in tensile tests, or a study of acoustic phenomena in tensile tests. Doctor of Philosophy, Technical University of Munich

Kong X, Wang E, Hu S et al (2017) Research on precursory characteristics of critical slowing down before the failure of coal samples containing methane. J China Univ Min Technol 46:1–17

Li D, Wang E, Kong X et al (2019) Mechanical behaviors and acoustic emission fractal characteristics of coal specimens with a pre-existing flaw of various inclinations under uniaxial compression. Int J Rock Mech Min Sci 116:38–51

Li P, Cai M, Wang P et al (2021) Mechanical properties and energy evolution of jointed rock specimens containing an opening under uniaxial loading. Int J Miner Metall Mater 28:1875–1886

Liu X, Liu Y, Lu Y, Kou M (2020) Experimental and numerical study on pre-peak cyclic shear mechanism of artificial rock joints. Struct Eng Mech 74:407–423

Liu HY, Huang YS, Dan ZZM (2013) Test study on effect of joint on rock mass mechanical property. Appl Mech Mater 256:235–239. https://doi.org/10.4028/www.scientific.net/AMM.256-259.235

Lockner D, Byerlee J, Kuksenko V et al (1991) Quasi-static fault growth and shear fracture energy in granite. Nature 350:39–42

Moradian Z, Ballivy G, Rivard P et al (2010) Evaluating damage during shear tests of rock joints using acoustic emissions. Int J Rock Mech Min Sci 47:590–598

Naderloo M, Moosavi M, Ahmadi M (2019) Using acoustic emission technique to monitor damage progress around joints in brittle materials. Theor Appl Fract Mech 104:102368

Obert L (1941) Use of subaudible noises for prediction of rock bursts. US Department of the Interior, Bureau of Mines

Pan J, Wu X, Guo Q et al (2020) Uniaxial experimental study of the deformation behavior and energy evolution of conjugate jointed rock based on AE and DIC methods. Adv Civ Eng 2020:1–16

Poeck E, Garvey R, Zhang K, Ozbay U (2015) Contribution of shear slip in a widespread compressive pillar failure. In: ARMA US Rock Mechanics/Geomechanics Symposium. ARMA, p ARMA-2015

Potyondy DO, Cundall P (2004) A bonded-particle model for rock. Int J Rock Mech Min Sci 41:1329–1364

Seto M, Sato H, Sato M, Kono M (1988) Hypocenter distributions of AE in coal under uniaxial compression. Nippon Kogyo Kaishi Japan 104(3):163–168

Shemirani AB, Haeri H, Sarfarazi V, Hedayat A (2017) A review paper about experimental investigations on failure behaviour of non-persistent joint. Geomech Eng 13:535–570

ShengWang HAO, YiLong BAI, MengFen XIA, FuJiu KE (2014) Catastrophic rupture of quasi-brittle solids and its precursors. Sci Sin Phys Mech Astron 44:1262–1274. https://doi.org/10.1360/SSPMA2014-00115

Shi G-H (1991) Manifold method of material analysis. In: Transactions of the 9th army conference on applied mathematics and computing. US Army Research Office Minneapolis, Minn, USA

Shkuratnik V, Filimonov YL, Kuchurin S (2004) Experimental investigations into acoustic emission in coal samples under uniaxial loading. J Min Sci 40:458–464

Shkuratnik V, Nikolenko P, Koshelev A (2017) Spectral characteristics of acoustic emission in loaded coal specimens for failure prediction. J Min Sci 53:818–823

Singh M, Singh B, Choudhari J, Goel R (2004) Constitutive equations for 3-D anisotropy in jointed rocks and its effect on tunnel closure. Int J Rock Mech Min Sci 41:652–657

Singh S, Sharma S, Kwatra N (2022) A novel damage index for reinforced concrete beam-column joint using acoustic emission technique. Eur J Environ Civ Eng 26:8321–8345

Song W, Fu J (2018) A damage constitutive model and strength criterion of rock mass considering the dip angle of joints. Chin J Rock Mech Eng 37:2253–2263

Wang X, Meng F (2018) Statistical analysis of large accidents in China’s coal mines in 2016. Nat Hazards 92:311–325

Wang Y, Deng H, Deng Y et al (2021) Study on crack dynamic evolution and damage-fracture mechanism of rock with pre-existing cracks based on acoustic emission location. J Pet Sci Eng 201:108420

Wawersik WR, Fairhurst C (1970) A study of brittle rock fracture in laboratory compression experiments. Int J Rock Mech Min Sci Geomech Abstr 7:561–575. https://doi.org/10.1016/0148-9062(70)90007-0

Wen J, Tang Z, Dyson AP, Tolooiyan A (2021) The mechanical behaviour of pre-existing transverse cracks in lignite under uniaxial compression. Geomech Geophys Geo-Energy Geo-Resour 7:1–17

Xiong L, Chen H, Li T, Zhang Y (2018) Experimental study on the uniaxial compressive strength of artificial jointed rock mass specimen after high temperatures. Geomech Geophys Geo-Energy Geo-Resour 4:201–213

Yang S-Q, Yang Z, Zhang P-C, Tian W-L (2020) Experiment and peridynamic simulation on cracking behavior of red sandstone containing a single non-straight fissure under uniaxial compression. Theor Appl Fract Mech 108:102637

Yin D, Meng X (2019) Numerical simulation on uniaxial compression failure of a roof rock–coal–floor rock composite sample with coal persistent joint. Geotech Geol Eng 37:13–23

Yin DW, Chen SJ, Chen B et al (2018) Strength and failure characteristics of the rock-coal combined body with single joint in coal. Geomech Eng 15:1113–1124

Yuan Y, Fu J, Wang X, Shang X (2020) Experimental study on mechanical properties of prefabricated single-cracked red sandstone under uniaxial compression. Adv Civ Eng 2020:1–14. https://doi.org/10.1155/2020/8845368

Zhang J-Z, Zhou X-P (2020) Forecasting catastrophic rupture in brittle rocks using precursory AE time series. J Geophys Res Solid Earth 125:e2019JB019276. https://doi.org/10.1029/2019JB019276

Zhang J, Huang P, Zhang Q et al (2017) Stability and control of room mining coal pillars—taking room mining coal pillars of solid backfill recovery as an example. J Cent South Univ 24:1121–1132

Zhang J-Z, Wu W-T, Zhou X-P (2023a) On the predictability of localization instabilities of quasibrittle materials from accelerating rates of acoustic emission. Eng Fract Mech 289:109455. https://doi.org/10.1016/j.engfracmech.2023.109455

Zhang J-Z, Zhou X-P, Du Y-H (2023b) Cracking behaviors and acoustic emission characteristics in brittle failure of flawed sandstone: a true triaxial experiment investigation. Rock Mech Rock Eng 56:167–182. https://doi.org/10.1007/s00603-022-03087-0

Zhang T, Chen Q-Z, Zhang J-Z, Zhou X-P (2023c) Influences of mechanical contrast on failure characteristics of layered composite rocks under true-triaxial stresses. Rock Mech Rock Eng 56:5363–5381. https://doi.org/10.1007/s00603-023-03341-z

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