Liu, HY, Small, JC & Carter, JP 2008, 'Effects of Tunnelling on Existing Support Systems of Intersecting Tunnels in the Sydney Region ', in Y Potvin, J Carter, A Dyskin & R Jeffrey (eds), Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium
, Australian Centre for Geomechanics, Perth, pp. 113-126.
Full three-dimensional (3D) elasto-plastic finite element analyses are conducted to investigate the effects of tunnelling on existing tunnel support systems, i.e. shotcrete lining and rockbolts, of orthogonally intersecting tunnels in the Sydney region with a high horizontal regional stress regime. It is found that the zone of influence extends about 2.5 tunnel diameters (2.5D) from the intersection. During driving of the new tunnel, the existing support system in the zone of influence is affected according to the progression of the new tunnel face to/from the existing tunnel and the effects are not significant when the new tunnel face is located 4.5D from the intersection. The approach of the new tunnel face towards the existing tunnel causes the existing shotcrete lining on the approach side of the existing tunnel to undergo tensile cracking, while neither further compressive failures nor further tensile cracking is observed when the new tunnel is driven away from the existing tunnel. It is suggested that temporary reinforcement should be installed inside the zone of influence during approach and local thickening of the shotcrete lining of the existing tunnel is necessary in locations immediately adjacent to the intersection.
Augarde, C.E. (1997) Numerical modelling of tunnelling processes for assessment of damage to buildings. Department of Engineering Science, University of Oxford, pp. 39–40.
Augarde, C.E. and Burd, H.J. (2001) Three-dimensional finite element analysis of lined tunnels. International Journal for Numerical and Analytical Methods in Geomechanics 25, pp. 243–262.
Benzley, S.E., Perry, E., Merkley, K., Clark, B. and Sjaardama, G. (1995) A comparison of all hexagonal and all tetrahedral finite element meshes for elastic and elasto-plastic analysis. Proceedings 4th International Meshing Roundtable Albuquerque, New Mexico, Sandia National Laboratories, pp. 179–191.
Bonnier, P.G., Moller, S.C. and Vermeer, P.A. (2002) Bending moments and normal forces in tunnel linings. 5th European Conference Numerical Methods in Geotechnical Engineering (NUMGE 2002), Paris: Presses de l'ENPC/LCPC, pp. 515–522.
Entrekin, A. (1999) Accuracy of MSC/NASTRAN first- and second-order tetrahedral elements in solid modelling for stress analysis. MSC Aerospace Users' Conference, USA, pp. 1–8.
Gercek, H. (1986) Stability considerations for underground excavation intersections. Mining Science and Technology 4, pp. 49–57.
Hsiao, F.Y., Yu, C.W. and Chen, J.C. (2005) Modelling the behaviours of the tunnel intersection areas adjacent to the ventilation shafts in the Hsuehshan tunnel. World Long Tunnel 2005, Taiwan, China, pp. 81–90.
Japan Nuclear Cycle Development Institute (JNC) (1999) Supporting report 2: Repository design and engineering technology. H12: Project to establish the scientific and technical basis for HLW disposal in Japan, Japan.
Lee, P.S., Noh, H.C. and Bathe, K.J. (2007) Insight into 3-node triangular shell finite elements: the effects of element isotropy and mesh patterns. Computers and Structures 85, pp. 404–418.
Liu, H.Y., Small, J.C. and Carter, J.P. (2008a) Full 3D modelling for effects of tunnelling on existing support systems in the Sydney region. Tunnelling and Underground Space Technology 23, pp. 399–420.
Liu, H.Y., Small, J.C. and Carter, J.P. (2008b) Effects of tunnelling on existing support systems of perpendicularly crossing tunnels. Computers and Geotechnics (c0urrently in revision).
Mashimo, H., Isago, N., Yoshinaga, S., Shiroma, H. and Baba, K. (2002) Experimental investigation on load-carrying capacity of concrete tunnel lining. 28th ITA General Assembly and World Tunnel Congress (AITES-ITA DOWNUNDER 2002), pp. 1–10.
Pells, P.J.N. (2002) Developments in the design of tunnels and caverns in the Triassic rocks of the Sydney region. International Journal of Rock Mechanics and Mining Sciences 39(5), pp. 569–587.
Pottler, R. (1992) Three-dimensional modelling of junctions at the channel tunnel project. International Journal for Numerical and Analytical Methods in Geomechanics 16, pp. 683–695.
Sjoberg, J., Perman, F., Leander, M. and Saiang, D. (2006) Three-dimensional analysis of tunnel intersections for a train tunnel under Stockholm. Proceeding 2006 North American Tunnelling Conference, Ozdemir L. (editor), Taylor & Francis Group, London, pp. 39–48.
Swoboda, G., Shen, X.P. and Rosas, L. (1998) Damage model for jointed rock mass and its application to tunnelling. Computers and Geotechnics 22(3/4), pp. 189–203.
Tsuchiyama, S., Hayakawa, M., Shinokawa, T. and Konno, H. (1988) Deformation behaviour of the tunnel under the excavation of crossing tunnel. Proceedings 6th International Conference on Numerical Methods in Geomechanics. Innsbruck, Balkema, Rotterdam, pp. 1591–1596.
WorkCover (2005) Lane Cove Tunnel collapse and subsidence. WorkCover Authority of New South Wales, Australia, November, 2005.