Geomechanics and Engineering

  • 제15권5호
  • /
  • Pages.1113-1124
  • /
  • 2018
  • /
  • 2005-307X(pISSN)
  • /
  • 2092-6219(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Strength and failure characteristics of the rock-coal combined body with single joint in coal

  • Yin, Da W. (College of Mining and Safety Engineering, Shandong University of Science and Technology) ;
  • Chen, Shao J. (College of Mining and Safety Engineering, Shandong University of Science and Technology) ;
  • Chen, Bing (College of Mining and Safety Engineering, Shandong University of Science and Technology) ;
  • Liu, Xing Q. (College of Mining and Safety Engineering, Shandong University of Science and Technology) ;
  • Ma, Hong F. (College of Mining and Safety Engineering, Shandong University of Science and Technology)
  • 투고 : 2017.04.29
  • 심사 : 2018.01.14
  • 발행 : 2018.08.10
⟨ 이전 논문 다음 논문 ⟩

초록

Geological dynamic hazards during deep coal mining are caused by the failure of a composite system consisting of the rock and coal layers, whereas the joint in coal affects the stability of the composite system. In this paper, the compression test simulations for the rock-coal combined body with single joint in coal were conducted using $PFC^{2D}$ software and especially the effects of joint length and joint angle on strength and failure characteristics in a rock-coal combined body were analyzed. The joint length and joint angle exhibit a deterioration effect on the strength and affect the failure modes. The deterioration effect of joint length of L on the strength can be neglected with a tiny variation at ${\alpha}$ of $0^{\circ}$ or $90^{\circ}$ between the loading direction and joint direction. While, the deterioration effect of L on strength are relatively large at ${\alpha}$ between $30^{\circ}$ and $60^{\circ}$. And the peak stress and peak strain decrease with the increase of L. Additionally, the deterioration effect of ${\alpha}$ on the strength becomes larger with the increase of L. With the increase of ${\alpha}$, the peak stress and peak strain first decrease and then increase, presenting "V-shaped" curves. And the peak stress and peak strain at ${\alpha}$ of $45^{\circ}$ are the smallest. Moreover, the failure mainly occurs within the coal and no apparent failure is observed for rock. At ${\alpha}$ between $30^{\circ}$ and $60^{\circ}$, the secondary shear cracks generated in or close to the joint tips, cause the structural instability failure of the combined body. Therefore, their failure models present as a shear failure along partial joint plane direction and partially cutting across the coal body or a shear failure along the joint plane direction. However, at ${\alpha}$ of $60^{\circ}$ and L of 10 mm, the "V-shaped" shear cracks cutting across the coal body cause its final failure. While crack nucleations at ${\alpha}$ of $0^{\circ}$ or $90^{\circ}$ are randomly distributed in the coal, the failure mode shows a V-shaped shear failure cutting across the coal body.

키워드

과제정보

연구 과제 주관 기관 : National Natural Science Foundation of China, Shandong Provincial Natural Science Fundation, Shandong University of Science and Technology, Natural Science Foundation of Shandong Province, Shandong Provience University

참고문헌

  1. Cao, R.H., Cao, P., Lin, H., Pu, C.Z. and Ou, K. (2016), "Mechanical behavior of brittle rock-like specimens with preexisting fissures under uniaxial loading, experimental studies and particle mechanics approach", Rock Mech. Rock Eng., 49(3), 763-783. https://doi.org/10.1007/s00603-015-0779-x
  2. Chen, S.J., Yin, D.W., Cao, F.W., Liu, Y. and Ren, K.Q. (2016), "An overview of integrated surface subsidence-reducing technology in mining areas of China", Nat. Hazards, 81(2), 1129-1145. https://doi.org/10.1007/s11069-015-2123-x
  3. Chen, S.J., Yin, D.W., Zhang, B.L., Ma, H.F. and Liu, X.Q. (2017), "Study on mechanical characteristics and progressive failure mechanism of roof-coal pillar structure body", Chin. J. Rock Mech. Eng., 36(7), 1588-1598 (in Chinese).
  4. Huang, B.X. and Liu J.W. (2013), "The effect of loading rate on the behavior of samples composed of coal and rock", J. Rock Mech. Min. Sci., 61, 23-30. https://doi.org/10.1016/j.ijrmms.2013.02.002
  5. Landriani, G.S. and Taliercio, A. (1987), "A note on failure conditions for layered materials", Meccanica, 22(2), 97-102. https://doi.org/10.1007/BF01556908
  6. Liang, Z.Z., Xing, H., Wang, S.Y., Williams, D.J. and Tang, C.A. (2012), "A three-dimensional numerical investigation of the fracture of rock specimens containing a pre-existing surface flaw", Comput. Geotech., 45(9), 19-33. https://doi.org/10.1016/j.compgeo.2012.04.011
  7. Liu, J., Wang, E.Y., Song, D.Z., Wang, S.H. and Niu, Y. (2015), "Effect of rock strength on failure mode and mechanical behavior of composite samples", Arab. J. Geosci., 8(7), 4527-4539. https://doi.org/10.1007/s12517-014-1574-9
  8. Lee, H. and Jeon, S. (2011), "An experimental and numerical study of fracture coalescence in pre-cracked specimens under uniaxial compression", J. Solids Struct., 48(6), 979-999. https://doi.org/10.1016/j.ijsolstr.2010.12.001
  9. Lu, C.P., Liu, G.J., Liu, Y., Zhang, N., Xue, J.H. and Zhang, L. (2015), "Microseismic multi-parameter characteristics of rockburst hazards induced by hard roof fall and high sress concentration", J. Rock Mech. Min. Sci., 76, 18-32. https://doi.org/10.1016/j.ijrmms.2015.02.005
  10. Manouchehrian, A., Sharifzadeh, M., Marji, M.F. and Gholamnejad, J. (2014), "A bonded particle model for analysis of the flaw orientation effect on crack propagation mechanism in brittle materials under compression", Arch. Civ. Mech. Eng., 14(1), 40-52. https://doi.org/10.1016/j.acme.2013.05.008
  11. Mishra, B. and Verma, P. (2015), "Uniaxial and triaxial single and multistage creep tests on coal-measure shale rocks", J. Coal Geol., 137, 55-65 https://doi.org/10.1016/j.coal.2014.11.005
  12. Mohammadi, M. and Tavakoli, H. (2015), "Comparing the generalized Hoek-Brown and Mohr-Coulomb failure criteria for stress analysis on the rocks failure plane", Geomech. Eng., 9(1), 115-124. https://doi.org/10.12989/gae.2015.9.1.115
  13. Kulatilake, P., Malama, B. and Wang, J. (2001), "Physical and particle flow modeling of jointed rock block behavior under uniaxial loading", J. Rock Mech. Min. Sci., 38(5), 641-657. https://doi.org/10.1016/S1365-1609(01)00025-9
  14. Park, J.W. and Song, J.J. (2009), "Numerical simulation of a direct shear test on a rock joint using a bonded-particle model", J. Rock Mech. Min. Sci., 46(8), 1315-1328. https://doi.org/10.1016/j.ijrmms.2009.03.007
  15. Petukhov, I.M. and Linkov, A.M. (1979), "The theory of postfailure deformations and the problem of stability in rock mechanics", J. Rock Mech. Min. Sci. Geomech. Abstr., 16(2), 57-76.
  16. Potyondy, D.O. and Cundall, P.A. (2004), "A bonded-particle model for rock", J. Rock Mech. Min. Sci., 41(8), 1329-1364. https://doi.org/10.1016/j.ijrmms.2004.09.011
  17. Tian, W.L., Yang, S.Q. and Huang, Y.H. (2017), "An experiment and particle flow study of Brazilian disk containing two noncoplanar filled fissures", J. China Univ. Min. Technol., 46(3), 537-545 (in Chinese).
  18. Yang, S.Q. (2015), "An experimental study on fracture coalescence characteristics of brittle sandstone specimens combined various flaws", Geomech. Eng., 8(4), 541-557. https://doi.org/10.12989/gae.2015.8.4.541
  19. Yang, S.Q. and Huang, Y.H. (2014), "Experiment and particle flow simulation on crack coalescence behavior of sandstone specimens containing double holes and a single fissure", J. Basic Sci. Eng., 22(3), 584-597 (in Chinese).
  20. Yi, C., Zhu, H.G., Wang, H.T., Liu, Z. and Pan, H. (2011), "Analysis of transformation conditions and influence factors of uni-body and bi-body models under axial compression", Rock Soil Mech., 32(5), 1297-1376 (in Chinese).
  21. Yin, D.W., Chen, S.J., Liu, X.Q. and Ma, H.F. (2018), "Effect of joint angle in coal on failure mechanical behavior of rock-coal combined body", Quart. J. Eng. Geol. Hydrogeol., 51(2), 202-209. https://doi.org/10.1144/qjegh2017-041
  22. Zhang, Z.P. and Wong, L.N.Y. (2012), "Cracking processes in rock-like material containing a single flaw under uniaxial compression: A numerical study based on parallel bondedparticle model approach", Rock Mech. Rock Eng., 45(5), 711-737. https://doi.org/10.1007/s00603-011-0176-z
  23. Zhao, T.B., Guo, W.Y., Lu, C.P. and Zhao, G.M. (2016), "Failure characteristics of combined coal-rock with different interfacial angles", Geomech. Eng., 11(3), 345-359. https://doi.org/10.12989/gae.2016.11.3.345
  24. Zhao, Z.H., Wang, W.M., Dai, C.Q. and Yan, J.X. (2014), "Failure characteristics of three-body model composed of rock and coal with different strength and stiffness", Trans. Nonferr. Metal. Soc. Chin., 24(5), 1538-1546. https://doi.org/10.1016/S1003-6326(14)63223-4
  25. Zhao, W.H., Huang, R.Q. and Yan, M. (2015), "Mechanical and fracture behavior of rock mass with parallel concentrated joints with different dip angle and number based on PFC simulation", Geomech. Eng., 8(6), 757-767. https://doi.org/10.12989/gae.2015.8.6.757
  26. Zhu, C.Q., Ma, X.F., Zhang, X.F. and Guo, F. (2014), "Effect of single closed crack on coal and rock mass fracture behavior under uniaxial compression", Safety Coal Mines, 10, 169-172 (in Chinese).
  27. Zuo, J.P., Xie, H.P., Meng, B.B. and Liu, J.F. (2011), "Experimental research on loading-unloading behavior of coalrock combination bodies at different stress levels", Rock Soil Mech., 32(5), 1287-1296 (in Chinese).

피인용 문헌

  1. An Experimental Study of the Uniaxial Failure Behaviour of Rock-Coal Composite Samples with Pre-existing Cracks in the Coal vol.2019, pp.None, 2018, https://doi.org/10.1155/2019/8397598
  2. Mechanical Response of Listric Faults in the Three Gorges Reservoir Area Based on Three-Dimensional Morphological Characteristics vol.9, pp.None, 2018, https://doi.org/10.3389/fphy.2021.766920