Summary
During the crossing of brittle rock formations at the Lötschberg base tunnel, failure phenomena have been observed both at the tunnel face and at the walls. A detailed analysis has been undertaken to explain these behaviours, based on the recent developments of Canadian research on brittle failure mechanisms. At the tunnel walls, a very good agreement is found between the calculated and observed damage and between two prediction methods, i.e. a semi-empirical failure criterion and elastic calculations with the “brittle Hoek-Brown parameters.” Near the face, due to the 3D nature of the stress conditions, some limitations of these approaches have been highlighted, and the growth of wall failure has been analysed. This research allowed a better understanding of the brittle rock mass behaviour at the Lötschberg base tunnel and showed that brittle failure processes dominate the behaviour of deep, highly stressed excavations in massive to moderately jointed rock. It also illustrates where improvements to the adopted approaches are required.
Similar content being viewed by others
References
Barton N (1994) A Q-system case record of cavern design in faulted rock. In: Tunnelling in difficult ground, Torino, Italy, 8 pp
Diederichs MS, Kaiser PK, Martin CD (2000) The use of discrete element simulation to illuminate brittle rock failure process. In: Proceedings of the 53rd Canadian Geotechnical Conference, Montreal, Canada, p 447–454
MS Diederichs PK Kaiser E Eberhardt (2004) ArticleTitleDamage initiation and propagation in hard rock during tunnelling and the influence of near-face stress rotation Int J Rock Mech Mining Sci 41 IssueID5 785–812 Occurrence Handle10.1016/j.ijrmms.2004.02.003
E Eberhardt (2001) ArticleTitleNumerical modelling of three-dimension stress rotation ahead of an advancing tunnel face Int J Rock Mech Mining Sci 38 499–518 Occurrence Handle10.1016/S1365-1609(01)00017-X
AA Griffith (1924) Theory of rupture Proceedings of the 1st international congress applied mechanics Delft The Netherlands 55–63
VR Hajiabdolmajid PK Kaiser CD Martin (2002) ArticleTitleModelling brittle failure of rock Int J Rock Mech Mining Sci 39 731–741 Occurrence Handle10.1016/S1365-1609(02)00051-5
VR Hajiabdolmajid PK Kaiser CD Martin (2003) ArticleTitleMobilised strength components in brittle failure of rock Geotechnique 53 IssueID3 327–336 Occurrence Handle10.1680/geot.53.3.327.37280
H Horii S Nemat-Nasser (1985) ArticleTitleCompression-induced microcrack growth in brittle solids: axial splitting and shear failure J Geophys Res 90 IssueIDB4 3105–3125 Occurrence Handle10.1029/JB090iB04p03105
IGWS (1995) Décompressions violentes: évaluation des zones à risques. Report RA14 for BLS AlpTransit AG Lötschberg Basislinie, 155 pp
PK Kaiser (2002) Lötschberg tunnel: rockburst hazard assessment—contribution to project R487 MIRARCO, Laurentian University Canada 22
Kaiser PK (2005) Tunnel stability in highly stressed, brittle ground—rock mechanics considerations for Alpine tunnelling. In: Keynote lecture, Geological AlpTransit Symposium (GEAT’05), Zürich, Switzerland, 20 pp
Kaiser PK (2006) Rock mechanics consideration for construction of deep tunnel in brittle ground. In: Keynote lecture, Asian Rock Mechanics Symposium, Singapore, 12 pp
PK Kaiser DR McCreath DD Tannant (1996) Canadian rockburst support handbook Mining Research Directorate Sudbury, Canada 314
PK Kaiser MS Diederichs CD Martin J Sharp W Steiner (2000) Underground works in hard rock tunnelling and mining Keynote lecture at GeoEng2000, Melbourne Australia Technomic Publishing Co. Melbourne, Australia 841–926
CD Martin (1997) ArticleTitleSeventeenth Canadian Geotechnical Colloquium: the effect of cohesion loss and stress path on brittle rock strength Can Geotech J 34 IssueID5 698–725 Occurrence Handle10.1139/cgj-34-5-698
CD Martin B Stimpson (1994) ArticleTitleThe effect of sample disturbance on laboratory properties of Lac du Bonnet granite Can Geotech J 31 IssueID5 692–702 Occurrence Handle10.1139/t94-081
CD Martin PK Kaiser DR McCreath (1999) ArticleTitleHoek-Brown parameters for predicting the depth of brittle failure around tunnels Can Geotech J 36 IssueID1 136–151 Occurrence Handle10.1139/cgj-36-1-136
CD Martin PK Kaiser R Christiansson (2003) ArticleTitleStress, instability and design of underground excavations Int J Rock Mech Mining Sci 40 1027–1047 Occurrence Handle10.1139/t94-081
Müller B, Reinecker J, Heidbach O, Fuchs K (2004) The 2004 release of the world stress map. Available online at: http://www.world-stress-map.org
Rojat F, Labiouse V, Descoeudres F, Kaiser PK (2002) Brittle rock failure at the Loetschberg, Steg sector (AlpTransit tunnel). Project R487. Rock Mechanics Laboratory of EPFL, Lausanne
Switzerland Z_Soil v5.71 (2002) User’s manual. ZACE, Lausanne, Switzerland
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Rojat, F., Labiouse, V., Kaiser, P. et al. Brittle Rock Failure in the Steg Lateral Adit of the Lötschberg Base Tunnel. Rock Mech Rock Eng 42, 341–359 (2009). https://doi.org/10.1007/s00603-008-0015-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00603-008-0015-z