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KSCE Journal of Civil Engineering

, Volume 22, Issue 9, pp 3278–3291 | Cite as

Experimental and Numerical Study on the Damage Evolution Behaviour of Granitic Rock during Loading and Unloading

  • Bing Dai
  • Guoyan Zhao
  • H. Konietzky
  • P. L. P. Wasantha
Geotechnical Engineering
  • 88 Downloads

Abstract

Theoretical and experimental studies have revealed that the damage evolution plays an important role in stability of rock structures. To investigate the damage characteristics of rocks during loading and unloading, a series of conventional triaxial tests and numerical simulations were conducted on granitic rock specimens under different confining pressures. The stress-strain characteristics and fracture patterns of tested specimens were first analyzed. It was found that the failure strain in unloading is smaller than the failure strain in loading. And the difference between the two strains is growing with increasing confining pressure. The failure patterns of specimens displayed two different failure mechanisms: a single distinct failure and a “X” failure. Based on the law of energy conservation, the energy evolution was analyzed. The results indicated that absorbed strain energy converted into elastic strain energy and dissipation energy. For evaluating and predicting damage, two damage degrees were proposed considering increase of dissipation energy and decrease of tangential modulus, respectively. The results show that before the reversal point of volumetric strain, the damage degrees were almost unchanged. During the process of unloading the damage degrees increases fast. For the same strain, lower confining pressure shows more damage. It indicates that the confining pressure has negative effects on increase of the damage degree. Then, the discrete element model based on elastic and unbreakable voronoi blocks was set-up for tri-axial tests. The energy evolution and damage process were simulated. And the ratio of failed contacts was used to simulate the damage degree. It shows that stress-strain behavior as well as micro- and macro-mechanical damage evolution can be reproduced by the DEM model.

Keywords

triaxial test loading and unloading energy damage degree numerical simulation 

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References

  1. Alzo’ubi, A. K. (2012). “Modeling of rocks under direct shear loading by using discrete element method.” Alhosn University Journal of Engineering & Applied Sciences, Vol. 4, pp. 5–20.Google Scholar
  2. Ayling, M. R., Meredith, P. G., and Murrell, S. A. (1995). “Microcracking during triaxial deformation of porous rocks monitored by changes in rock physical properties, I.” Elastic-wave Propagation Measurements on Dry Rocks. Tectonophysics, Vol. 245, No. 3, pp. 205–221, DOI: 10.1016/0040-1951(94)00236-3.Google Scholar
  3. Baud, P. and Meredith, P. G. (1997). “Damage accumulation during triaxial creep of Darley Dale sandstone from pore volumometry and acoustic emission.” International Journal of Rock Mechanics and Mining Sciences, Vol. 34, No. 3, pp. 24–31, DOI: 10.1016/S1365-1609(97)00060-9.Google Scholar
  4. Bieniawski, Z. T. (1967, October). “Mechanism of brittle fracture of rock: part I—theory of the fracture process.” In International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, Vol. 4, No. 4, pp. 395IN11405–404IN12406. DOI: 10.1016/0148-9062(67)90030-7.CrossRefGoogle Scholar
  5. Cai, M., Kaiser, P. K., Tasaka, Y., Maejima, T., Morioka, H., and Minami, M. (2004). “Generalized crack initiation and crack damage stress thresholds of brittle rock masses near underground excavations.” International Journal of Rock Mechanics and Mining Sciences, Vol. 41, No. 5, pp. 833–847, DOI: 10.1016/j.ijrmms.2004.02.001.CrossRefGoogle Scholar
  6. Chen, W. and Konietzky, H. (2014). “Simulation of heterogeneity, creep, damage and lifetime for loaded brittle rocks.” Tectonophysics, Vol. 633, pp. 164–175, DOI: 10.1016/j.tecto.2014.06.033.CrossRefGoogle Scholar
  7. Chen, W., Konietzky, H., Tan, X., and Frühwirt, T. (2016). “Pre-failure damage analysis for brittle rocks under triaxial compression.” Computers and Geotechnics, Vol. 74, pp. 45–55, DOI: 10.1016/j.compgeo.2015.11.018.CrossRefGoogle Scholar
  8. Christianson, M., Board, M., and Rigby, D. (2006). “UDEC simulation of triaxial testing of lithophysal tuff.” In Golden Rocks 2006, the 41st US Symposium on Rock Mechanics (USRMS). American Rock Mechanics Association.Google Scholar
  9. Cundall, P. A. (1980). UDEC-A Generalised Distinct Element Program for Modelling Jointed Rock (No. PCAR-1-80), Cundall associates Virginia water.Google Scholar
  10. Debecker, B. and Vervoort, A. (2013). “Two-dimensional discrete element simulations of the fracture behaviour of slate.” International Journal of Rock Mechanics and Mining Sciences, Vol. 61, pp. 161–170, DOI: 10.1016/j.ijrmms.2013.02.004.CrossRefGoogle Scholar
  11. Dai, B., Zhao, G., Dong, L., and Yang, C. (2015). “Mechanical characteristics for rocks under different paths and unloading rates under confining pressures.” Shock and Vibration, DOI: 10.1155/2015/578748.Google Scholar
  12. Eberhardt, E., Stead, D., Stimpson, B., and Read, R. S. (1998). “Identifying crack initiation and propagation thresholds in brittle rock.” Canadian Geotechnical Journal, Vol. 35, No. 2, pp. 222–233, DOI: 10.1139/cgj-35-2-22.CrossRefGoogle Scholar
  13. Eberhardt, E., Stead, D., and Stimpson, B. (1999). “Quantifying progressive pre-peak brittle fracture damage in rock during uniaxial compression.” International Journal of Rock Mechanics and Mining Sciences, Vol. 36, No. 3, pp. 361–380, DOI: 10.1016/S0148-9062(99)00019-4.CrossRefGoogle Scholar
  14. Gang, W., Jun, S., and Wu, Z. R. (1997). “Damage mechanical analysis of unloading failure of intact rock mass under complex stress state.” Journal of Hehai University, Vol. 25, No. 3, pp. 44–49. (in Chinese)Google Scholar
  15. Guo, Y. T., Yang, C. H., and Fu, J. J. (2012). “Experimental research on mechanical characteristics of salt rock under tri-axial unloading test.” Rock and Soil Mechanics, Vol. 33, No. 3, pp. 725–732. (in Chinese)Google Scholar
  16. Gu, R. and Ozbay, U. (2013). UDEC analysis of unstable rock failure in shear and compressive loading.Google Scholar
  17. Huang, R. Q. and Huang, D. (2010). “Experimental research on affection laws of unloading rates on mechanical properties of Jinping marble under high geostress.” Chinese Journal of Rock Mechanics and Engineering, Vol. 29, No. 1, pp. 21–33. (in Chinese)MathSciNetGoogle Scholar
  18. Huang, D. and Li, Y. (2014). “Conversion of strain energy in triaxial unloading tests on marble.” International Journal of Rock Mechanics and Mining Sciences, Vol. 66, pp. 160–168, DOI: 10.1016/j.ijrmms.2013.12.001.CrossRefGoogle Scholar
  19. Lajtai, E. Z., Carter, B. J., and Duncan, E. S. (1991). “Mapping the state of fracture around cavities.” Engineering Geology, Vol. 31, No. 3, pp. 277–289, DOI: 10.1016/0013-7952(1)90012-A.CrossRefGoogle Scholar
  20. Li, X., Cao, W., Zhou, Z., and Zou, Y. (2014). “Influence of stress path on excavation unloading response.” Tunnelling and Underground Space Technology, Vol. 42, pp. 237–246, DOI: 10.1016/j.tust.2014.03.002.CrossRefGoogle Scholar
  21. Li, J., W, M. Y., Fan P. X., and Shi, C. C. (2012). “Study of loading-unloading states and energy distribution relationship for rock mass.” Rock and Soil Mechanics, Vol. 33, No. Supp. 2, pp. 125–132. (in Chinese)CrossRefGoogle Scholar
  22. Martino, J. B. and Chandler, N. A. (2004). “Excavation-induced damage studies at the underground research laboratory.” International Journal of Rock Mechanics and Mining Sciences, Vol. 41, No. 8, pp. 1413–1426, DOI: 10.1016/j.ijrmms.2004.09.010.CrossRefGoogle Scholar
  23. Ma, M. and Brady, B. H. (1999). “Analysis of the dynamic performance of an underground excavation in jointed rock under repeated seismic loading.” Geotechnical & Geological Engineering, Vol. 17, No. 1, pp. 1–20, DOI: 10.1023/A:1008864329747.CrossRefGoogle Scholar
  24. Park, E. S., Martin, C. D., and Christiansson, R. (2004). “Simulation of the mechanical behavior of discontinuous rock masses using a bonded-particle model.” In Gulf Rocks 2004, the 6th North America Rock Mechanics Symposium (NARMS). American Rock Mechanics Association.Google Scholar
  25. Peng, R., Ju, Y., Wang, J. G., Xie, H., Gao, F., and Mao, L. (2015). “Energy dissipation and release during coal failure under conventional triaxial compression.” Rock Mechanics and Rock Engineering, Vol. 48, No. 2, pp. 509–526, DOI: 10.1007/s00603-014-0602-0.CrossRefGoogle Scholar
  26. Qiuling, H. A. (1998). “Loading and unloading rock masses mechanics.” Chinese Journal of Geotechnical Engineering, Vol. 20, No. 1, pp. 114. (in Chinese)Google Scholar
  27. Qiu, S. L., Feng, X. T., Zhang, C. Q., Zhou, H., and Sun, F. (2010). “Experimental research on mechanical properties of deep-buried marble under different unloading rates of confining pressures.” Chinese Journal of Rock Mechanics and Engineering, Vol. 29, No. 9, pp. 1807–1817. (in Chinese)Google Scholar
  28. Rellesmann, O. (1957). “Rock mechanics in regard to static loading caused by mining excavation.” In The 2nd US Symposium on Rock Mechanics (USRMS). American Rock Mechanics Association.Google Scholar
  29. Schmidtke, R. H. and Lajtai, E. Z. (1985). “The long-term strength of Lac du Bonnet granite.” In International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, Vol. 22, No. 6, pp. 461–465, DOI: 10.1016/0148-9062(85)90010-5.CrossRefGoogle Scholar
  30. Shao, S., Ranjith, P. G., Wasantha, P. L. P., and Chen, B. K. (2015). “Experimental and numerical studies on the mechanical behaviour of Australian Strathbogie granite at high temperatures: An application to geothermal energy.” Geothermics, Vol. 54, pp. 96–108, DOI: 10.1016/j.geothermics.2014.11.005.CrossRefGoogle Scholar
  31. Sun, D. A., Matsuoka, H., Muramatsu, D., Hara, T., Kudo, A., Yoshida, Z., and Takezawa, S. (2004). “Deformation and strength characteristics of weathered soft rock using triaxial tests.” International Journal of Rock Mechanics and Mining Sciences, Vol. 41, pp. 87–92, DOI: 10.1016/j.ijrmms.2004.03.024.CrossRefGoogle Scholar
  32. Tan, X., Konietzky, H., Frühwirt, T., and Dan, D. Q. (2015). “Brazilian tests on transversely isotropic rocks: Laboratory testing and numerical simulations.” Rock Mechanics and Rock Engineering, Vol. 48, No. 4, pp. 1341–1351, DOI: 10.1007/s00603-014-0629-2.CrossRefGoogle Scholar
  33. Tan, X. and Konietzky, H. (2014). “Numerical study of variation in Biot's coefficient with respect to microstructure of rocks.” Tectonophysics, Vol. 610, pp. 159–171, DOI: 10.1016/j.tecto.2013.11.014.CrossRefGoogle Scholar
  34. Thasnanipan, N., Maung, A. W., Tanseng, P., and Wei, S. H. (1998). Performance of a braced excavation in Bangkok clay, diaphragm wall subject to unbalanced loading conditions.Google Scholar
  35. Ulusay, R. and Hudson, J. A. ISRM (2007). The complete ISRM suggested methods for rock characterization, testing and monitoring: 1974–2006. Commission on testing methods, International Society of Rock Mechanics, Compilation arranged by the ISRM Turkish National Group, Ankara, Turkey.Google Scholar
  36. Wahl, M. H., McKellar, H. N., and Williams, T. M. (1997). “Patterns of nutrient loading in forested and urbanized coastal streams.” Journal of Experimental Marine Biology and Ecology, Vol. 213, No. 1, pp. 111–131, DOI: 10.1016/S0022-0981(97)00012-9.CrossRefGoogle Scholar
  37. Wasantha, P. L. P. and Ranjith, P. G. (2014). “Water-weakening behavior of Hawkesbury sandstone in brittle regime.” Engineering Geology, Vol. 178, pp. 91–101, DOI: 10.1016/j.enggeo.2014.05.015.CrossRefGoogle Scholar
  38. Wu, G. and Zhang, L. (2004). “Studying unloading failure characteristics of a rock mass using the disturbed state concept.” International Journal of Rock Mechanics and Mining Sciences, Vol. 41, pp. 419–425, DOI: 10.1016/j.ijrmms.2004.03.077.CrossRefGoogle Scholar
  39. Xie, H. P., Peng, R. D., and Ju, Y. (2005). “On energy analysis of rock failure.” Chinese Journal of Rock Mechanics and Engineering, Vol. 24, No. 15, pp. 2603–2608. (in Chinese)Google Scholar
  40. Xie, H. P., Ju, Y., Li, L. Y., and Peng, R. D. (2008). “Energy mechanism of deformation and failure of rock masses.” Chin J Rock Mech Eng., Vol. 27, No. 9, pp. 1729–1739. (in Chinese)Google Scholar
  41. Zhang, K., Zhou, H., Pan, P. Z., Shen, L. F., Feng, X. T., and Zhang, Y. G. (2010). “Characteristics of strength of rocks under different unloading rates.” Rock and Soil Mechanics, Vol. 31, No. 7, pp. 2072–2078. (in Chinese)Google Scholar
  42. Zhao, X. G., Wang, J., Cai, M., Cheng, C., Ma, L., K., Su, R., Zhao, F., and Li, D. J. (2014). “Influence of unloading rate on the strain burst characteristics of Beishan granite under true triaxial unloading conditions.” Rock Mechanics and Rock Engineering, Vol. 47, No 2, pp. 467–483, DOI: 10.1007/s00603-013-0443-2.CrossRefGoogle Scholar
  43. Zhao, G. Y., Bing, D. A. I., Dong, L. J., and Chen, Y. A. N. G. (2015). “Energy conversion of rocks in process of unloading confining pressure under different unloading paths.” Transactions of Nonferrous Metals Society of China, Vol. 25, No. 5, pp. 1626–1632, DOI: 10.1016/S1003-6326(15)63767-0.CrossRefGoogle Scholar

Copyright information

© Korean Society of Civil Engineers 2018

Authors and Affiliations

  • Bing Dai
    • 1
    • 2
    • 3
  • Guoyan Zhao
    • 3
  • H. Konietzky
    • 2
  • P. L. P. Wasantha
    • 2
  1. 1.Nuclear Resources Engineering CollegeUniversity of South ChinaHengyangChina
  2. 2.Institut für GeotechnikTechnische Universität Bergakademie FreibergFreibergGermany
  3. 3.School of Resources and Safety EngineeringCentral South UniversityChangshaChina

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