Application of Norwegian Method of Tunnelling (NMT) Principles to bypass landslides in mountainous terrain

  • Published : 2020.03.20

Abstract

Tunnelling to bypass major landslide areas is considered as a good and long-term environmentally friendly solution to reduce an existing hazard. In Norway, hundreds of kilometres of tunnels have been constructed in areas prone to landslides and snow avalanches. Although tunnelling is considered as an expensive mitigation strategy for bypassing landslides, analysis indicate that in some cases the cost of building a tunnel can be repaid by savings in driving costs (fuel) alone over a period of 5-10 years due to reduced driving distances. The other benefits of constructing tunnels in landslide areas include savings in time and increased safety. The Norwegian Method of Tunnelling (NMT) is considered safe, efficient and cost effective compared to other tunnelling techniques. Some aspects of NMT, which are considered safe and cost efficient, are presented. The application of updated rock support techniques, including reinforced ribs of shotctrete (RRS), which is a key component of the Norwegian Method of Tunnelling (NMT), is highlighted.

Keywords

References

  1. Barton, N., R. Lien and J. Lunde, 1974, "Engineering classification of rock masses for the design of tunnel support", Rock Mechanics, Vol. 6, No. 4, pp. 189-236. https://doi.org/10.1007/BF01239496
  2. Barton, N., Grimstad, E., Aas, G., Opsahl, O.A., Bakken, A., Pedersen, L., and Johansen, E.D., 1992. Norwegian Method of Tunneling, WT Focus on Norway, World Tunneling, June/August 1992.
  3. Barton, N. and Grimstad, E. 2014. Tunnel and cavern support selection in Norway, based on rock mass classification with the Q-system. Norwegian Tunneling Technology Publication No. 23, Norwegian Tunneling Society.
  4. Berggren, A., Nermoen, B., Kveen, A., Jakobsen, P.D. and Neby, A. 2014. Excavation and support methods, Norwegian Tunneling Technology, Publication No. 23, Norwegian Tunneling Society.
  5. Bhasin, R., Grimstad, E., Aarset, A. and Malik, S. (2019). Overcoming rock engineering challenges for construction of transport tunnels in the Himalayas. Proceedings American Rock Mechanics Association, New York, 2019, Paper ARMA 19-1616.
  6. Bhasin, R. and Loset, F. and Barton, N., (1999). Rock Support Performance of a Sub-Sea Tunnel in Western Norway. Proc. third International Symposium on Sprayed Concrete Gol, Norway, September 1999, pp.58-69.
  7. Bhasin, R., Grimstad, E., Larsen, J.O., Dhawan, A.K., Singh, R. and Verma, S.K. 2002. Landslide Hazards and Mitigation Measures at Gangtok, Sikkim Himalaya. Engineering Geology, Vol. 64, pp. 351-368. https://doi.org/10.1016/S0013-7952(01)00096-5
  8. Bhasin, R., Tshering, T. and Olsson, R. 2012. The Effect of Earthquake on Rock Support in Tunnels. World Tunnel Congress 2012, Bangkok, Thailand, 20-23 May 2012, Tunnelling and underground Space for a Global Society.
  9. Bhasin, R., Pabst, T. and Aarset, A. (2017) Detailed engineering geological investigations and numerical modelling for a planned road tunnel in Bhutan Himalaya. Proc. World Tunnel Congress 2017 - Surface challenges - Underground solutions. Bergen, Norway.
  10. Grimstad, E., Barton, N. 1993. Updating the Q-system for NMT. International Symposium on Sprayed Concrete. Fagernes, September 1993. Proceedings, pp. 46-66. Norsk Betongforening/NIF, Oslo 1993.
  11. Grimstad, E. 1986. Rock-Burst problems in road tunnels. Norwegian Road Tunneling, Publication no. 4, Norwegian Soil and Rock Engineering Association, Tapir Publishers, N-7034 Trondheim.
  12. Grimstad, E. and KvKle, J. 1999. The influence of Rock Stress and Support on the Depth of the Disturbed Zone in the Laerdal Tunnel. A key to Differentiate the Rock Support. Proceedings pp. 341-346. ITA Conference, Oslo June 1999.
  13. Grimstad, E., Bhasin, R., Hagen, A.W., Kaynia, A. and Kankes, K., (2003) Q-system advance for sprayed lining. Tunnels and Tunneling International (pp. 44-47), January 2003.
  14. NGI, 2015. Using the Q-system, Rock mass classification and support design. Handbook, published at ww.ngi.no, 2015.
  15. NPRA Norwegian Public Roads Administration. 2010. Technical Report No. 2538. Works ahead of the tunnel face and rock support in road tunnels, NPRA, Oslo (Norwegian).