Risk Quantification for Tunnel Excavation Process

Authors: J. Šejnoha, D. Jarušková, O. Špačková, E. Novotná

Abstract:

Construction of tunnels is connected with high uncertainty in the field of costs, construction period, safety and impact on surroundings. Risk management became therefore a common part of tunnel projects, especially after a set of fatal collapses occurred in 1990's. Such collapses are caused usually by combination of factors that can be divided into three main groups, i.e. unfavourable geological conditions, failures in the design and planning or failures in the execution. This paper suggests a procedure enabling quantification of the excavation risk related to extraordinary accidents using FTA and ETA tools. It will elaborate on a common process of risk analysis and enable the transfer of information and experience between particular tunnel construction projects. Further, it gives a guide for designers, management and other participants, how to deal with risk of such accidents and how to make qualified decisions based on a probabilistic approach.

Keywords: risk quantification, tunnel collapse, ETA, FTA, geotechnical risk

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1058151

References:

1] S.D. Eskesen, P. Tengborg, J. Kampmann, T.H. Veicherts, "Guidelines for tunnelling risk management: International Tunnelling Association, Working Group No. 2". Tunnelling and Underground Space Technology 19 (2004), pp. 217-237.
[2] The International Tunnelling Insurance Group, "A code of practice for risk management of tunnel works", January 2006. Available: http://www.munichre.com/publications/tunnel_code_of_practice_en.pdf
[3] S.Y. Min, T.K. Kim, J.S. Lee, H.H. Einstein, "Design and construction of a road tunnel in Korea including application of the Decision Aids for Tunneling, - A case study". Tunnelling and Underground Space Technology 23 (2008), pp. 91-102.
[4] S. Min, "Development of the resource model for the Decision Aids for Tunneling". Ph.D Theses, Massachusetts institute of Technology, February 2008.
[5] J.Y. Ruwanpura, S.T. Ariaratnam, "Simulation modeling techniques for underground infrastructure construction processes". Tunnelling and Underground Space Technology 22 (2007), pp. 553-567.
[6] F. Zhou, S.M. AbouRizk, S.Fernando, "A simulationtemplate for modeling tunnel shaft construction". Proceedings of the 2008 Winter Simulation Conference, pp. 2455-2461.
[7] E.S. Hong et al., "Quantitative risk evaluation based on event tree analysis technique: Application to the design of shield TBM". Tunnelling and Underground Space Technology 24 (2009), pp. 269-277.
[8] A.G. Benardos, D.C. Kaliampakos, "A methodology for assessing geotechnical hazards for TBM tunneling - illustrated by the Athens Metro, Greece". International Journal of Rock Mechanics & Mining Sciences 41 (2004), pp. 987-999.
[9] R. Sturk, L. Olsson, J. Johansson, "Risk and decision analysis for large underground projects, as applied to the Stockholm ring road tunnels". Tunnelling and Underground Space Technology 11 (1996), pp. 157-164.
[10] M.H.C. Chan, "A geological prediction and updating model in tunneling", M.S. theses, Dept. of Civil Engineering, MIT, 1981.
[11] R.E.Melchers, Structural reliability analysis and prediction, Chichester: John Wiley & Sons Ltd, reprinted 2001, ch. 6.
[12] OpenFTA Version 1.0 User Manual, Formal Software Construction Ltd., 2005.
[13] M.TichÛ, Risk control: Analysis and Management, Prague: C.H.Beck, 2006.