Structural Engineering and Mechanics

  • 제79권2호
  • /
  • Pages.237-245
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  • 2021
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  • 1225-4568(pISSN)
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  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Numerical simulation on the crack initiation and propagation of coal with combined defects

  • Lv, Huayong (School of Architecture and Engineering, Shangqiu Normal University) ;
  • Cheng, Zhanbo (School of Engineering, University of Warwick) ;
  • Dong, Yaqing (School of Architecture and Engineering, Shangqiu Normal University) ;
  • Zhang, Jing (School of Mathematics and Statistics, Shangqiu Normal University) ;
  • Ma, Yujie (School of Architecture and Engineering, Shangqiu Normal University)
  • 투고 : 2021.01.31
  • 심사 : 2021.05.30
  • 발행 : 2021.07.25
⟨ 이전 논문 다음 논문 ⟩

초록

There is normally the occurrence of pre-existing cracks and holes in coal mass to influence its mechanical behaviours. And the crack initiation and propagation around the tip of pre-existing cracks can be observed to induce the overall failure of coal mass finally. In this study, two groups of hole with the radius of 10mm connecting one crack with length and width of 20 mm and 1 mm, respectively, were pre-existed in sample to explore the influence of crack angle (from 0 to 90°) on the unconfined compressive strength (UCS), crack initiation and propagation, and failure modes of coal mass with combined faults by using RFPA2D. The results showed that the stress-strain curves of specimen with double-hole-crack exhibit multiple stress drop compared to that of intact coal sample, especially in the post-peak stage. Moreover, UCS decreased firstly with the crack angle increasing to 30° and then increased until the crack angle reaching to 75° following by decreasing with the continuous increase of crack angle to 90°. In addition, the failure mode of double-hole-crack specimen with the crack angle of 0-30° can be regards as the dominated tensile failure combined with shear failure, which was consist with the failure pattern of intact specimen. On the other hand, the failure mode of double-hole-crack specimen with the crack angle of 45-90° is the dominated shear failure combined with tensile failure. Meanwhile, the distribution characteristics of acoustic emission energy can be used to better reflect the deformation and failure process of coal mass with combined defects.

키워드

과제정보

The authors wish to acknowledge the financial support from National Natural Science Foundation of China under Grant No. 51674264, Research Startup Budget Funding Project of Shangqiu Normal University under Grant No. 700167 and China Scholarship Council (CSC). The authors would also like to thank the editors and anonymous reviewers for their valuable time and suggestions.

참고문헌

  1. Ai, D., Zhao, Y., Wang, Q. and Li, C. (2019), "Experimental and numerical investigation of crack propagation and dynamic properties of rock in SHPB indirect tension test", Int. J. Impact. Eng., 126, 135-146. https://doi.org/10.1016/j.ijimpeng.2019.01.001.
  2. Aria, M., Riccardo, S. andrea, M. and Marco, G. (2018), "Testing and numerical simulation of a medium strength rock material under unconfined compression loading", J. Rock Mech. Geotech., 10(2), 5-19. https://doi.org/10.1016/j.jrmge.2017.11.009.
  3. Benouis, A., Boulenouar, A., Benseddiq, N. and Serier, B. (2015), "Numerical analysis of crack propagation in cement PMMA, Application of SED approach", Struct. Eng. Mech., 55(1), 93-109. http://doi.org/10.12989/sem.2015.55.1.093.
  4. Berakova, A., Melichar, R. and Souek, K. (2020), "Mechanical properties and failure patterns of migmatized gneiss with metamorphic foliation under ucs test", Rock Mech. Rock Eng., 53(4), 2007-2013. https://doi.org/10.1007/s00603-019-02012-2.
  5. Bobet, A. (2000), "The initiation of secondary cracks in compression", Eng. Fract. Mech., 66(2), 187-219. https://doi.org/10.1016/S0013-7944(00)00009-6.
  6. Cao, R., Cao, P., Lin, H., Fan, X., Zhang, C. and Liu, T. (2019), "Crack initiation, propagation, and failure characteristics of jointed rock or rock-like specimens: A review", Adv. Civil Eng., 1-31. https://doi.org/10.1155/2019/6975751.
  7. Cen, D. and Huang, D. (2014), "Mesoscopic displacement modes of crack propagation of rock mass under uniaxial compression with high strain rate", J. Min. Saf. Eng., 39(3), 436-444.
  8. Chen, B., Zhang, S., Li, Y., Li, Z. and Zhou, H. (2020), "Physical simulation study of crack propagation and instability information discrimination of rock-like materials with faults", Arab. J. Geosci., 13(18), 1-14. https://doi.org/10.1007/s12517-020-05966-8
  9. Cheng, Z., Li, L. and Zhang, Y. (2020), "Laboratory investigation of the mechanical properties of coal-rock combined body", B. Eng. Geol. Environ., 79, 1947-1958. https://doi.org/10.1007/s10064-019-01613-z.
  10. Cheng, Z., Pan, W., Li, X. and Sun, W. (2019b), "Numerical simulation on strata behaviours of TCCWF influenced by coal-rock combined body", Geomech. Eng., 19(3), 269-282. https://doi.org/10.12989/gae.2019.19.3.269.
  11. Cheng, Z., Yang, S., Li, L. and Zhang, L. (2019a), "Support working resistance determined on top-coal caving face based on coal-rock combined body", Geomech. Eng., 19(3), 255-268. https://doi.org/10.12989/gae.2019.19.3.255.
  12. Cheng, Z., Zhang, Y., Li, L. and Lv, H. (2018), "Theoretical solution and analysis of the elastic modulus and foundation coefficient of coal-rock combination material", Int. J. Mater. Sci. Res., 1(1), 23-31. https://doi.org/10.18689/ijmsr-1000104
  13. Dong, W., Wu, Z., Zhou, X., Wang, N. and Kastiukas, G. (2017), "An experimental study on crack propagation at rock-concrete interface using digital image correlation technique", Eng. Fract. Mech., 171, 50-63. https://doi.org/10.1016/j.engfracmech.2016.12.003.
  14. Duriez, J., Scholtes, L. and Donze, F.V. (2016), "Micromechanics of wing crack propagation for different flaw properties", Eng. Fract. Mech., 153, 378-398. https://doi.org/10.1016/j.engfracmech.2015.12.034.
  15. Gholizadeh, S., Leman, Z. and Baharudin, B.T.H.T. (2015), "A review of the application of acoustic emission technique in engineering", Struct. Eng. Mech., 54(6), 1075-1095. https://doi.org/10.12989/sem.2015.54.6.1075.
  16. Guo, Q., Pan, J., Cai, M. and Zhang, Y. (2020), "Investigating the effect of rock bridge on the stability of locked section slopes by the direct shear test and acoustic emission technique", Sensor., 20(3), 638. https://doi.org/10.3390/s20030638.
  17. Haeri, H., Sarfarazi, V., Zhu, Z. and Lazemi, H.A. (2018), "Investigation of the effects of particle size and model scale on the UCS and shear strength of concrete using PFC2D", Struct. Eng. Mech., 67(5), 505-516. http://doi.org/10.12989/sem.2018.67.5.505.
  18. Kong, D., Cheng, Z. and Zheng, S. (2019), "Study on failure mechanism and stability control measures in large-cutting-height coal mining face with deep-buried seam", B. Eng. Geol. Environ., 78(8), 6143-6157. https://doi.org/10.1007/s10064-019-01523-0.
  19. Kong, D., Xiong, Y., Cheng, Z., Wang, N., Wu, G. and Liu, Y. (2021), "Stability analysis of coal face based on coal face-support-roof system in steeply inclined coal seam", Geomech. Eng., 25(3), 233-243. https://doi.org/10.12989/gae.2021.25.3.233.
  20. Lee, H. and Jeon, S. (2011), "An experimental and numerical study of fracture coalescence in pre-cracked specimens under uniaxial compression", Int. J. Solid. Struct., 48(6), 979-999. https://doi.org/10.1016/j.ijsolstr.2010.12.001.
  21. Li, D., Wang, E., Kong, X., Ali, M. and Wang, D. (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. Mining Sci., 116, 38-51. https://doi.org/10.1016/j.ijrmms.2019.03.022.
  22. Li, S., Zhang, D., Bai, X., Zhang, X., Chu, Y. and Guo, K. (2019), "Experimental study on mechanical properties, acoustic emission energies and failure modes of pre-cracked rock materials under uniaxial compression", Pure. Appl. Geophys., 176(10), 4519-4532. https://doi.org/10.1007/s00024-019-02201-8.
  23. Liu, R., Zhu, Z., Li, Y., Liu, B., Wan, D. and Li, M. (2020), "Study of rock dynamic fracture toughness and crack propagation parameters of four brittle materials under blasting", Eng. Fract. Mech., 225, 106460. https://doi.org/10.1016/j.engfracmech.2019.04.034.
  24. Liu, X. and Cheng, Z. (2019), "Changes in subsidence-field surface movement in shallow-seam coal mining", J. S. Afr. I. Min. Metal., 119(02), 201-206. http://doi.org/10.17159/2411-9717/2019/v119n2a12.
  25. Lv, H., Tang, Y., Zhang, L., Cheng, Z. and Zhang, Y. (2019), "Analysis for mechanical characteristics and failure models of coal specimens with non-penetrating single crack", Geomech. Eng., 17(4), 355-365. https://doi.org/10.12989/gae.2019.17.4.355.
  26. Lv. H., Cheng, Z. and Liu, F. (2021), "Study on the mechanism of a new fully mechanical mining method for extremely thick coal seam", Int. J. Rock Mech. Min., 142, 104788. https://doi.org/10.1016/j.ijrmms.2021.104788.
  27. Mirsayar, M.M., Razmi, A., Aliha, M.R.M. and Berto, F. (2018), "EMTSN criterion for evaluating mixed mode I/II crack propagation in rock materials", Eng. Fract. Mech., 190, 186-197. https://doi.org/10.1016/j.engfracmech.2017.12.014.
  28. Nabil, B., Abdelkader, B., Miloud, A. and Noureddine, B. (2017), "On the mixed-mode crack propagation in FGMs plates: comparison of different criteria", Struct. Eng. Mech., 61(3), 371-379. http://doi.org/10.12989/sem.2017.61.3.371.
  29. Oner, E., Yaylaci, M. and Birinci, A. (2015), "Analytical solution of a contact problem and comparison with the results from FEM", Struct. Eng. Mech., 54(4), 607-622. http://doi.org/10.12989/sem.2015.54.4.607.
  30. Ozturk, H. and Guner, D. (2019), "Laboratory and distinct element analysis of the deformability behaviour of thin spray-on liners", Int. J. Rock Mech. Min., 123, 104118. https://doi.org/10.1016/j.ijrmms.2019.104118.
  31. Saadat M. and Taheri, A. (2019), "A numerical approach to investigate the effects of rock texture on the damage and crack propagation of a precracked granite", Comput. Geotech., 111, 89-111. https://doi.org/10.1016/j.compgeo.2019.03.009.
  32. Sun, W., Du, H., Zhou, F. and Shao, J. (2019), "Experimental study of crack propagation of rock-like specimens containing conjugate fractures", Geomech. Eng., 17(4), 323-331. https://doi.org/10.12989/gae.2019.17.4.323.
  33. Tang, C. (2001), "Analysis of crack coalescence in rock-like materials containing three flaws-Part II: numerical approach", Int. J. Rock Mech. Min. Sci., 38(7), 925-939. https://doi.org/10.1016/S1365-1609(01)00065-X.
  34. Wang, H., Wu, Z., Wang, Y. and Rena, C. (2019), "An analytical method for predicting mode-I crack propagation process and resistance curve of rock and concrete materials", Theor. Appl. Fract. Mech., 100, 328-341. https://doi.org/10.1016/j.tafmec.2019.01.019.
  35. Xi, X., Wu, X., Guo, Q. and Cai, M. (2020), "Experimental investigation and numerical simulation on the crack initiation and propagation of rock with pre-existing cracks", IEEE Access, 8, 129636-129644. https://doi.org/10.1109/ACCESS.2020.3009230.
  36. Xie, Y., Cao, P., Liu, J. and Dong, L. (2016), "Influence of crack surface friction on crack initiation and propagation: A numerical investigation based on extended finite element method", Comput. Geotech., 74, 1-14. https://doi.org/10.1016/j.compgeo.2015.12.013.
  37. Xu, J. and Li, Z. (2019), "Crack propagation and coalescence of step-path failure in rocks", Rock. Mech. Rock. Eng., 52(4), 965-979. https://doi.org/10.1007/s00603-018-1661-4.
  38. Yang, S., Yang, Z., Zhang, P. and Tian, W. (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. https://doi.org/10.1016/j.tafmec.2020.10263.
  39. Yang, S., Yin, P., Zhang, Y., Chen, M., Zhou, X., Jing, H. and Zhang, Q. (2019), "Failure behavior and crack evolution mechanism of a non-persistent jointed rock mass containing a circular hole", Int. J. Rock Mech. Min. Sci., 114, 101-121. https://doi.org/10.1016/j.ijrmms.2018.12.017.
  40. Yaylaci, M. (2016), "The investigation crack problem through numerical analysis", Struct. Eng. Mech., 57(6), 1143-1156. http://doi.org/10.12989/sem.2016.57.6.1143.
  41. Zeng, W., Yang, S. and Tian, W. (2018), "Experimental and numerical investigation of brittle sandstone specimens containing different shapes of holes under uniaxial compression", Eng. Fract. Mech., 200, 430-450. https://doi.org/10.1016/j.engfracmech.2018.08.016.
  42. Zhang, Y., Cheng, Z. and Lv, H. (2019), "Study on failure and subsidence law of frozen soil layer in coal mine influenced by physical conditions", Geomech. Eng., 18(1), 97-109. https://doi.org/10.12989/gae.2019.18.1.097.
  43. Zhang, Z., Wang, S., Wang, C. and Wang, P. (2020), "A study on rock mass crack propagation and coalescence simulation based on improved numerical manifold method (NMM)", Geomech. Geophys. Geo., 7(1), 1-16. https://doi.org/10.1007/s40948-020-00193-7.
  44. Zhao, Y., Gong, S., Zhang, C., Zhang, Z. and Jiang, Y. (2018), "Fractal characteristics of crack propagation in coal under impact loading", Fract., 26(02), 1840014. https://doi.org/10.1142/S0218348X18400145.
  45. Zhou, L., Zhu, Z., Qiu, H., Zhang, X. and Lang, L. (2018), "Study of the effect of loading rates on crack propagation velocity and rock fracture toughness using cracked tunnel specimens", Int. J. Rock. Mech. Min. Sci., 112, 25-34. https://doi.org/10.1016/j.ijrmms.2018.10.011.
  46. Zhou, S., Zhuang, X., Zhu, H. and Rabczuk, T. (2018), "Phase field modelling of crack propagation, branching and coalescence in rocks", Theor. Appl. Fract. Mech., 96, 174-192. https://doi.org/10.1016/j.tafmec.2018.04.011.
  47. Zhuang, X., Chun, J. and Zhu, H. (2014), "A comparative study on unfilled and filled crack propagation for rock-like brittle material", Theor. Appl. Fract. Mech., 72, 110-120. https://doi.org/10.1016/j.tafmec.2014.04.004.