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Interaction between rock bolt and rock bridge under tensile loading

  • Sarfarazi, Vahab (Department of Mining Engineering, Hamedan University of Technology) ;
  • Asgari, Kaveh (Department of Mining Engineering, Shahid Bahonar University of Kerman) ;
  • Nasrollahi, Mehdi (Department of Civil Engineering, Azad University of Hamedan)
  • Received : 2021.01.05
  • Accepted : 2021.06.11
  • Published : 2021.06.25

Abstract

The objective of this study is investigating the effect of loading rates on the interaction between rock bolts and rock bridges using experimental test and numerical simulation. A new test set up was developed experimentally for determination of tensile strength of bridge area. A concrete block with dimensions of 15 × 15 × 10 cm consisting non-persistent notch was prepared and subjected to tensile loading using special loading set up. The configuration of non-persistent joint was different in various samples. A 30-ton hydraulic load cell applied tensile loading to concrete complex with a high-pressure rate of 0.01 mm per second. Simultaneously with experimental test, numerical simulation was performed on the tensile behavior of non-persistent joint adjacent to rock bolt. Two sets of non-persistent joint were prepared. The first sets were similar to experimental one while, in the second sets, two edge joints with lengths of 1.5 cm, 3 cm and 4.5 cm were prepared. The angle of these joint related to horizontal axis were 0, 15, 30, 45, 60, 75, and 90. Also, the rock bolts adjacent to joints were simulated and were subjected to tensile loading with two high and low loading rates i.e. 0.01 mm/sec and 0.0001 mm/sec. The results showed that the crack propagation angle related to tensile load direction was decreased by decreasing the tensile loading rate. The tensile failure stress decreased by presence of pre-existing crack within the model. Tensile failure stress had minimum value whenever the angle of pre-existing crack was 0°. The numerical results were in a good accordance with experimental ones.

Keywords

References

  1. Barton, N.R. (1986), "Deformation phenomena in jointed rock", Geotechnique, 36(2), 147-167. https://doi.org/10.1680/geot.1986.36.2.147.
  2. Cao, R., Yao, R., Meng, J., Lin, Q., Lin, H. and Li, S. (2020), "Failure mechanism of non-persistent jointed rock-like specimens under uniaxial loading: Laboratory testing", Int. J. Rock Mech. Min. Sci., 132, 90-104. https://doi.org/10.1016/j.ijrmms.2020.104341.
  3. Das, R., Sirdesai, N.N. and Singh, T.N. (2017), "Analysis of deformational behavior of circular underground opening in soft ground using three-dimensions al physical model", Proceedings of the 51st US Rock Mechanics/Geomechanics Symposium, San Francisco, California, U.S.A., June.
  4. Dias, D. (2011), "Convergence-confinement approach for designing tunnel face reinforcement by horizontal bolting", Tunn. Undergr. Sp. Tech., 26(4), 517-523. https://doi.org/10.1016/j.tust.2011.03.004.
  5. Forbes, B., Vlachopoulos, N., Hyett, A.J. amd Diederichs, M.S. (2017). "A new optical sensing technique for monitoring shear of rock bolts", Tunn. Undergr. Sp. Tech., 66, 34-46. https://doi.org/10.1016/j.tust.2017.03.007.
  6. Goel, R.K., Swarup, A. and Sheorey, P.R. (2007), "Bolt length requirement in underground openings", Int. J. Rock Mech. Min. Sci., 44(5), 802-811. https://doi.org/10.1016/j.ijrmms.2006.12.001.
  7. Hu, J., Wen, G., Lin, Q., Cao, P. and Li, S. (2020), "Mechanical properties and crack evolution of double-layer composite rocklike specimens with two parallel fissures under uniaxial compression", Theor. Appl. Fract. Mech., 108, 101-118. https://doi.org/10.1016/j.tafmec.2020.102610.
  8. Itasca Consulting Group Inc. (2002), Particle Flow Code in 2 Dimensions, Version 30, Itasca Consulting Group Inc., Minneapolis, Minnesota, U.S.A.
  9. Kim H., Kim K., Kim H. and Shin J. (2018) "Anchorage mechanism and pullout resistance of rock bolt in water-bearing rocks", Geomech. Eng., 15(3), 98-111. http://doi.org/10.12989/gae.2018.15.3.841.
  10. Li, C.C. (2017), "Principles of rock bolting design", J. Rock Mech. Geotech. Eng., 9(3), 396-414. http://doi.org/10.1016/j.jrmge.2017.04.002.
  11. Li, Z., Soga, K. and Wright, P. (2015), "Behaviour of cast-iron bolted tunnels and their modelling", Tunn. Undergr. Sp. Tech., 50, 250-269. https://doi.org/10.1016/j.tust.2015.07.015.
  12. Lin, Q., Cao, P., Cao, R., Lin, H. and Meng, J. (2020a), "Mechanical behavior around double circular openings in a jointed rock mass under uniaxial compression", Arch. Civ. Mech. Eng., 20(1), 33-45. https://doi.org/10.1007/s43452-020-00027-z.
  13. Lin, Q., Cao, P., Mao, S., Ou, C. and Cao, R. (2020b), "Fatigue behaviour and constitutive model of yellow sandstone containing pre-existing surface crack under uniaxial cyclic loading", Theor. Appl. Fract. Mech., 109, 111-128. https://doi.org/10.1016/j.tafmec.2020.102776.
  14. Lin, Q., Cao, P., Meng, J., Cao, R. and Zhao, Z. (2020c), "Strength and failure characteristics of jointed rock mass with double circular holes under uniaxial compression: Insights from discrete element method modelling", Theor. Appl. Fract. Mech., 109, 21-38. https://doi.org/10.1016/j.tafmec.2020.102692/
  15. Lin, Q., Cao, P., Wen, G., Meng, J., Cao, R. and Zhao, Z. (2021), "Crack coalescence in rock-like specimens with two dissimilar layers and pre-existing double parallel joints under uniaxial compression", Int. J. Rock Mech. Min. Sci., 139, 39-53. https://doi.org/10.1016/j.ijrmms.2021.104621.
  16. Luo, X., Cao, P., Lin, Q. and Li, S. (2021), "Mechanical behaviour of fracture-filled rock-like specimens under compression-shear loads: An experimental and numerical study", Theor. Appl. Fract. Mech., 113, 55-67. http://doi.org/10.1016/j.tafmec.2021.102935.
  17. Palmstrom, A. and Singh, R. (2001), "The deformation modulus of rock masses - Comparisons between in situ tests and indirect estimates", Tunn. Undergr. Sp. Tech., 16(2), 115-131. https://doi.org/10.1016/S0886-7798(01)00038-4.
  18. Potyondy, D.O. and Cundall, P.A. (2004), "A bonded-particle model for rock", Int. J. Rock Mech. Min. Sci., 41(8), 1329-1364. https://doi.org/10.1016/j.ijrmms.2004.09.011.
  19. Ramulu, M., Chakraborty, A.K. and Sitharam, T.G. (2009), "Damage assessment of basaltic rock mass due to repeated blasting in a railway tunnelling project - A case study", Tunn. Undergr. Sp. Tech., 24(2), 208-221. https://doi.org/10.1016/j.tust.2008.08.002.
  20. Saiang, D. and Nordlund, E. (2009), "Numerical analyses of the influence of blast-induced damaged rock around shallow tunnels in brittle rock", Rock Mech. Rock Eng., 42(3), 421-448. https://doi.org/10.1007/s00603-008-0013-1.
  21. Shen, B. and Barton, N. (1997). "The disturbed zone around tunnels in jointed rock Masses", Int. J. Rock Mech. Min. Sci., 34(1), 117-125. https://doi.org/10.1016/S1365-1609(97)80037-8
  22. Singh, M., Rao, K.S. and Ramamurthy, T. (2002), "Strength and deformational behaviour of a jointed rock mass", Rock Mech. Rock Eng., 35(1), 45-64. https://doi.org/10.1007/s006030200008.
  23. Singh, S.P. and Xavier, P. (2005). "Causes, impact and control of overbreak in underground excavations", Tunn. Undergr. Sp. Tech., 20(1), 63-71. https://doi.org/10.1016/j.tust.2004.05.004.
  24. Wang, H., Li, S., Wang, Q., Wang, D., Li, W., Liu, P., Li, X. and Chen, Y. (2019), "Investigating the supporting effect of rock bolts in varying anchoring methods in a tunnel", Geomech. Eng., 19(6), 115-123. http://doi.org/10.12989/gae.2019.19.6.485.
  25. Wang, W., Song, Q., Xu, C. and Gong, H. (2018), "Mechanical behaviour of fully grouted GFRP rock bolts under the joint action of pre-tension load and blast dynamic load", Tunn. Undergr. Sp. Tech., 73, 82-91. https://doi.org/10.1016/j.tust.2017.12.007.
  26. Zhao, T, Zhang, Y., Zhang, Q. and Tan, Y. (2018), "Analysis on the creep response of bolted rock using bolted burgers model", Geomech. Eng., 14(2), 68-77. http://doi.org/10.12989/gae.2018.14.2.141.
  27. Zou, F., Xia, Z. and Dan, H. (2016), "Theoretical solutions for displacement and stress of a circular opening reinforced by grouted rock bolts", Geomech. Eng., 11(3), 32-47. http://doi.org/10.12989/gae.2016.11.3.439.