DOI QR코드

DOI QR Code

Analysis of the mechanical properties and failure modes of rock masses with nonpersistent joint networks

  • Wu, Yongning (State Key Laboratory of Mining Disaster Prevention and Control, Shandong University of Science and Technology) ;
  • Zhao, Yang (State Key Laboratory of Mining Disaster Prevention and Control, Shandong University of Science and Technology) ;
  • Tang, Peng (State Key Laboratory of Mining Disaster Prevention and Control, Shandong University of Science and Technology) ;
  • Wang, Wenhai (State Key Laboratory of Mining Disaster Prevention and Control, Shandong University of Science and Technology) ;
  • Jiang, Lishuai (State Key Laboratory of Mining Disaster Prevention and Control, Shandong University of Science and Technology)
  • Received : 2021.04.22
  • Accepted : 2022.07.18
  • Published : 2022.08.10

Abstract

Complex rock masses include various joint planes, bedding planes and other weak structural planes. The existence of these structural planes affects the mechanical properties, deformation rules and failure modes of jointed rock masses. To study the influence of the parameters of a nonpersistent joint network on the mechanical properties and failure modes of jointed rock masses, synthetic rock mass (SRM) technology based on discrete elements is introduced. The results show that as the size of the joints in the rock mass increases, the compressive strength and the discreteness of the rock mass first increase and then decrease. Among them, the joints that are characterized by "small but many" joints and "large and clustered" joints have the most significant impact on the strength of the rock mass. With the increase in joint density in the rock mass, the compressive strength of rock mass decreases monotonically, but the rate of decrease gradually decreases. With the increase in the joint dip angle in rock mass, the strength of the rock mass first decreases and then increases, forming a U-shaped change rule. In the analysis of the failure mode and deformation of a jointed rock mass, the type of plastic zone formed after rock mass failure is closely related to the macroscopic displacement deformation of the rock mass and the parameters of the joints, which generally shows that the location and density of the joints greatly affect the failure mode and displacement degree of the jointed rock mass. The instability mechanism of jointed surrounding rock is revealed.

Keywords

Acknowledgement

The research of this study was sponsored by the State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines (SKLMRDPC20KF02), the National Natural Science Foundation of China (52074166) and the China Postdoctoral Science Foundation (2019M652436). The authors are grateful for their support.

References

  1. Bo, H.U. (2010), "Intelligent selection of mechanical of discontinuous jointed rock mass based on Ffine structure descriptions and numerical tests", Chinese Journal of Rock Mechanics and Engineering, Doctoral Dissertation, Ph. D. Thesis, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing.
  2. Cheng-Fu, G.U. and Wang, H. (2015), "numerical simulation of rock failure process under different crack distribution under action of compressive stress", Coal Technology.
  3. Cho, J.W., Kim, H., Jeon, S. and Min, K.B. (2012), "Deformation and strength anisotropy of Asan gneiss, Boryeong shale, and Yeoncheon schist", Int. J. Rock Mech. Min. Sci., 50, 158-169. https://doi.org/10.1016/j.ijrmms.2011.12.004.
  4. Deng, G., Xie, H., Gao, M., Li, C. and He, Z. (2020), "Numerical simulation on the evolution of mining-induced fracture network in a coal seam and its overburden under the top coal caving method", Adv. Civil Eng., 2020, Article ID 8833193. https://doi.org/10.1155/2020/8833193.
  5. Esmaieli, K., Hadjigeorgiou, J. and Grenon, M. (2010), "Estimating geometrical and mechanical REV based on synthetic rock mass models at Brunswick Mine", Int. J. Rock Mech. Min. Sci., 47(6), 915-926. https://doi.org/10.1016/j.ijrmms.2010.05.010.
  6. Fu, J.W., Zhang, X.Z., Zhu, W.S., Chen, K. and Guan, J.F. (2017), "Simulating progressive failure in brittle jointed rock masses using a modified elastic-brittle model and the application", Eng. Fract. Mech., 178, 212-230. https://doi.org/10.1016/j.engfracmech.2017.04.037.
  7. Harthong, B., Scholtes, L. and Donze, F.V. (2012), "Strength characterization of rock masses, using a coupled DEM-DFN model", Geophys. J. Int., 191(2), 467-480. https://doi.org/10.1111/j.1365-246X.2012.05642.x.
  8. Huang, J., Safari, R., Lakshminarayanan, S., Mutlu, U. and McClure, M. (2014), "Impact of discrete fracture network (DFN) reactivation on productive stimulated rock volume: Microseismic, geomechanics and reservoir coupling", 48th US Rock Mechanics/Geomechanics Symposium. OnePetro, June.
  9. Huang, Y.H. (2016), "An experimental study on fracture mechanical behavior of rock-like materials containing two unparallel fissures under uniaxial compression", Acta Mechanica Sinica, 32(3), 442-455. https://doi.org/10.1007/s10409-015-0489-3.
  10. Huang, Y.H. and Yang, S.Q. (2015), "Discrete element study on strength and failure behavior of jointed sandstone with two sets of cross-joints", J. China Coal Soc., 40(1), 76-84.
  11. Inc, I. (2013), 3DEC-3D Distinct Element Code, Version 5.0, User's Manual.
  12. Ivars, D.M., Pierce, M.E., Darcel, C., Reyes-Montes, J., Potyondy, D.O., Young, R.P. and Cundall, P.A. (2011), "The synthetic rock mass approach for jointed rock mass modelling", Int. J. Rock Mech. Min. Sci., 48(2), 219-244. https://doi.org/10.1016/j.ijrmms.2010.11.014.
  13. Li, S., Wang, G., Wang, S., Yang, W. and Wang, X. (2006), "Application of fracture-damage model to anchorage of discontinuous jointed rockmass of excavation and supporting", Chin. J. Rock Mech. Eng., 25(8), 1582-1590. https://doi.org/10.3321/j.issn:1000-6915.2006.08.010
  14. Li, Y., Zhou, H., Dong, Z., Zhu, W., Li, S. and Wang, S. (2018), "Numerical investigations on stability evaluation of a jointed rock slope during excavation using an optimized DDARF method", Geomech. Eng., 14(3), 271-281. https://doi.org/10.12989/gae.2018.14.3.271.
  15. Liu, S.G., Liu, H.N., Wang, S.J., Hu, B. and Zhang, X.P. (2008), "Direct shesar tests and PFC2D numerical simulation of intermittent joints", Chin. J. Rock Mech. Eng., 27(9), 1828-1836. https://doi.org/10.3321/j.issn:1000-6915.2008.09.010
  16. Mughieda, O.S. (1997), "Failure mechanisms and strength of non-persistent rock joints", University of Illinois at Urbana-Champaign.
  17. Olofsson, I. and Fredriksson, A. (2005), "Strategy for a numerical Rock Mechanics Site Descriptive Model. Further development of the theoretical/numerical approach", Technical Report, SKBR-05-43, Sweden.
  18. Qing-Bin, M.E.N.G., Li-Jun, H.A.N., Wei-Guo, Q.I.A.O., DengGe, L.I.N. and Lie-Chang, W.E.I. (2012), "Numerical simulation of cross-section shape optimization design of deep soft rock roadway under high stress", J. Min. Saf. Eng., 29(5), 650-656.
  19. Shu, J., Jiang, L., Kong, P. and Wang, Q. (2019), "Numerical analysis of the mechanical behaviors of various jointed rocks under uniaxial tension loading", Appl. Sci., 9(9), 1824. https://doi.org/10.3390/app9091824.
  20. Wang, J. et al. (2019), "Analysis of damage evolution characteristics of jointed rock mass with different joint dip angles", Journal of Harbin Institute of Technology.
  21. Wang, P.X., Cao, P., Pu, C.Z., Fan, X. and Wang, C.C. (2017), "Effect of the density and inclination of joints on the strength and deformation properties of rock-like specimens under uniaxial compression", Chin. J. Eng., 39(4), 494-501.
  22. Yang, H., Liu, B. and Karekal, S. (2021), "Experimental investigation on infrared radiation features of fracturing process in jointed rock under concentrated load", Int. J. Rock Mech. Min. Sci., 139, 104619. https://doi.org/10.1016/j.ijrmms.2021.104619.
  23. Yin, S.H., Wu, A.X. and Li, X.W. (2012), "Orthogonal polar difference analysis for sensitivity of the factors influencing the ore pillar stability", J. China Coal Soc., 37, 48-52.
  24. Zeng, L. et al. (2019), "Optimization of loosing circle support of stoping roadway with large inclination", Mod. Tunnel. Technol., 56(3), 102-107.
  25. Zhao, Y., Wu, Y., Xu, Q., Jiang, L., Huang, W., Zhang, P. and Niu, Z. (2020), "Numerical analysis of the mechanical behavior and failure mode of jointed rock under uniaxial tensile loading", Adv. Civil Eng., 2020, Article ID 8811282. https://doi.org/10.1155/2020/8811282.
  26. Zhu, W.C., Tang, C.A., Yang, T.H. and Liang, Z.Z. (2003), "Constitutive relationship OF mesoscopic elements used in RFPA~(2D) and its validations", Chin. J. Rock Mech. Eng., 22(1), 24-29. https://doi.org/10.3321/j.issn:1000-6915.2003.01.004