Influence of Rock Properties in Estimating Rock Strength for Shallow Underground Structures in Weak Rocks

Didi Supriadi Agustawijaya

Abstract


DOI: 10.17014/ijog.5.2.93-105Two popular rock strength criteria, the linear Coulomb and non-linear Hoek-Brown, are widely used in underground designs. These two criteria may be applied differently depending on rock conditions. Weak rocks may have different properties compared to hard rocks. Both criteria have been applied in a current research to practically determine the applicability of the criteria in estimating the strength of weak rock masses of five shallow underground structures. Results show that both criteria are able to model the strength of the five weak rock masses, but as expected the criteria provide quite different values for each type of rocks. The strength of rock masses around underground structures depends on uniaxial compressive strength and confinement; but the linear criterion very much depends on shear characteristics of rock materials. Whereas, the non-linear criterion relies on the geological strength index (GSI). Although the GSI may have served practical descriptions for rock masses, some difficulties were found when using the GSI for very weak pyroclastic rocks. The GSI seems to provide underestimated indexes for these rock types. Estimations show that the non-linear criterion may not really exhibit curved strength envelopes rather linear in some sense, for five weak rock masses. Thus in general, when an underground structure is reasonably shallow, has a lack of confinement, and where the shear behaviour dominates rock failures, the linear criterion is more preferable than the non-linear criterion in modelling the strength of weak rock masses.

Keywords


rock property; strength criterion; weak rock; shallow underground structure; shear characteristic

References


Agustawijaya, D.S., 2002. The Development of Design Criteria for Underground Excavations in Coober Pedy Arid Soft Rocks. Ph.D. Thesis at the University of South Australia, Adelaide - South Australia.

Agustawijaya, D.S., Meyers, A., and Priest, S.D., 2004. Engineering properties of Coober Pedy rocks. Australian Geomechanics, 39 (1), p.19-27.

Agustawijaya, D.S., 2007. The uniaxial compressive strength of soft rock. Civil Engineering Dimension, 9 (1), p.9-14.

Agustawijaya, D.S., 2011. The influence of rock properties and size into strength criteria: A proposed criterion for soft rock masses. Civil Engineering Dimension, 13 (2), p.75-81.

Al-Awad, M.N.J., 2012. Evaluation of Mohr-Coulomb failure criterion using unconfined compressive strength. Proceedings of 7th Asian Rock Mechanics Symposium, Seoul, Korea.

Brady, B.H.G. and Brown, E.T., 1993. Rock Mechanics for Underground Mining, 2nd Edition. Chapman and Hall, London, 571pp.

Craig, R.F., 1994. Soil Mechanics. Chapman & Hall, London, 427pp.

Deere, D.U., Miller, R.P., 1966. Engineering Classification and Index Properties for Intact Rock, Technical Report No. AFWLTR- 65-116 December 1966, University of Illinois Urbana, Illinois, Contract AF 29 (601)-6319, 302pp.

Duran, A., 2016. Rock mass assessment - what goes wrong?. In: Dight, P.M. (ed.), Proceedings of APSSIM 2016 Australian Centre for Geomechanics, Perth, p.493-506. https://papers.acg.uwa.edu.au/p/1604_32_Duran/ [16 October 2017].

Eberhardt, E., 2012. ISRM suggested method: The Hoek-Brown failure criterion. Rock Mechanics and Rock Engineering, 45, p.981–988, DOI: 10.1007/s00603-012-0276-4.

Hoek, E. and Brown, E.T., 1994. Underground Excavations in Rock. Chapman & Hall, London, 527pp.

Hoek, E. and Brown, E.T., 1997. Practical estimates of rock mass strength. International Journal of Rock Mechanics and Mining Sciences, 34 (8), p.1165-1186. DOI:10.1016/S1365-1609(97)80069-X

Hoek, E. and Marinos, P., 2007. A brief history of the development of the Hoek-Brown failure criterion. The New Brazilian Journal of Soil and Rocks, Nov. 2, p.1-11.

Hoek, E., 2007. Practical Rock Engineering, e-book. Rocscience.com, https://www.rocscience.com/documents/hoek/corner/Practical-Rock-Engineering-Full-Text.pdf [2 March 2018].

Hoek, E., Carranza-Torres, C., and Corkum, B., 2002. Hoek-Brown failure criterion – 2002 edition. Proceedings of NARMS-TAC Conference, Toronto, p.267-273.

Hoek, E., Marinos, P., and Benissi, M., 1998. Applicability of the geological strength index (GSI) classification for very weak and sheared rock masses: The case of the Athens Schist Formation. Bulletin Engineering Geology and Environment, 57, p.151-160. DOI:10.1007/s100640050031

International Society for Rock Mechanics (ISRM), 1981. In: Brown ET (Ed), Rock Characterization, Testing and Monitoring, ISRM Suggested Methods. Pergamon Press, Oxford.

Jaiswal, A. and Shrivastva, B.K., 2012. A generalized three-dimensional failure criterion for rock masses. Journal of Rock Mechanics and Geotechnical Engineering, 4 (4), p.333-343. DOI:10.3724/SP.J.1235.2012.00333

Kavvadas, M., Hewison, L.R., Laskaratos, P.G., Seferoglou, C., and Michalis, I., 1996. Experiences from the construction of the Athens Metro. International Symposium on Geotechnical Aspects of Underground Construction in Soft Ground, London, p.1-7.

Labuz, J.F. and Zang, A., 2012. ISRM suggested method: Mohr-Coulomb failure criterion. Rock Mechanics and Rock Engineering, 45, p.975-979. DOI: 10.1007/s00603-012-0281-7

Mangga, S.A, Atmawinata, S., Hermanto, B., and Amin, T.C, 1994. Geological Map of Lombok Sheet, Nusa Tenggara, scale 1:250.000. Geological Research and Development Centre, Bandung.

Marinos, P. and Hoek, E., 2001. Estimating the geotechnical properties of heterogeneous rock masses such as Flysch. Bulletin Engineering Geology and Environment, 60, p.85-92.

Marinos, P. and Hoek, E., 2002. GSI: A geologically friendly tool for rock mass strength estimation. http://www.geoplanning.it/test/wp-content/uploads/2012/02/GSI.pdf [16 October 2017].

Marinos, V., Marinos, P., and Hoek, E., 2005. The geological strength index: applications and limitations. Bulletin Engineering Geology and Environment, 64, p.55-65. DOI:10.1007/s10064-004-0270-5

Martin, C.D., Kaiser, P.K., and Christiansson, R., 2003. Stress, instability and design of underground excavations. International Journal of Rock Mechanics and Mining Sciences. DOI:10.1016/S1365-1609(03)00110-2.

Martin, C.D., Kaiser, P.K., and McCreath, D.R., 1999a. Hoek-Brown parameters for predicting the depth of brittle failure around tunnels. Canadian Geotechnical Journal, 36, p.136-151. DOI:10.1139/t98-072

Martin, C.D., Tannant, D.D., and Yazici, P.K., 1999b. Stress path and instability around mine openings. 9th ISRM Congress, Paris, August, p.25-28. DOI:10.1201/NOE0415450287.ch2

Priest, S.D., 1993. Discontinuity Analysis for Rock Engineering, Chapman & Hall, London, 473pp.

Priest, S.D., 2005. Determination of shear strength and three-dimensional yield strength for the Hoek–Brown criterion. Rock Mechanics and Rock Engineering, 38 (4), p.299-327. DOI:10.1007/978-94-011-1498-1

Stiros, S.C.and Kontogianni, V.A., 2009. Coulomb stress changes: From earthquake to underground excavation failures, International Journal of Rock Mechanics and Mining Sciences, 46, p.182-187. DOI: 10.1016/j.ijrmms.2008.09.013

Sudradjat, A., Mangga, S.A., and Suwarna, N., 1998. Geological Map of the Sumbawa Sheet, Nusa Tenggara, scale 1:250.000. Geological Research and Development Centre, Bandung.

Yavuz, H., 2006. Support pressure estimation for circular and non-circular openings based on a parametric numerical modeling study. The Journal of the South African Institution of Mining Metallurgy, 106, p.129-138.


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