- Volume 25 Issue 6
DOI QR Code
Study on the Convergence of the NATM Tunnel Constructed in the Weathered Granite
풍화 화강암 지반에 건설된 NATM터널에서의 내공변위 연구
- Received : 2015.12.04
- Accepted : 2015.12.17
- Published : 2015.12.31
Predicting and measuring tunnel convergence is very crucial for estimating tunnel stability and economical construction of NATM tunnels. The method to estimate the tunnel convergence that occurs before and after construction is proposed based on literature reviews. The total displacement occurring related to tunnel construction is determined to be about 2.5 times that of measured displacements. The results of displacement measurements at two tunnels constructed with similar rock types are examined for the investigation of factors affecting the tunnel convergence. The average convergence of Gyungju A Tunnel is about 6.7 times bigger than that of Daejeon B Tunnel. The possible causes of the large convergence in Gyungju A Tunnel are suggested. In order to predict the convergence of tunnels, careful investigation of the geological structures in the ground surface and the influence of external conditions as well as careful face mapping of the tunnel face should be conducted.
Tunnel convergence;Rock mass ratings;Field measurements
- Chae, K.S., Lee, S.P., Lee, C.H.,and Han, S.J., 2011, Application and development trend of OTDRs, Tunnels and Underground Space, Korean Society for Rock Mechanics, Vol. 21, No. 1, 1-10 (in Korean).
- Chung, H.S., Kim, S.H., Lee, S.D., and Kim, N.Y., 1998, Prediction of ultimate displacement in tunnel using statistical method, Proceedings of the National Conference of the Korean Geotechnical Society, 347-356 (in Korean).
- Franklin, J.A., 1976, An observational approach to the selection and control of rock tunnel linings, Proc. Conf. Shotcrete Ground Control, ASCE, Easton, MA, 556-596.
- Hanafy, E.A. and Emery, J.J., 1980, Advancing face simulation of tunnel excavations and lining placement, 13th Canadian Rock Mechanics Symposium, CIMM, Montreal, 119-125.
- Jang, W.Y., Yang, H.S., Chung, S.K., 2008, Longitudinal deformation profile in tunnel using measured data, Tunnels and Underground Space, Korean Society for Rock Mechanics, Vol. 18, No. 5, 338-342 (in Korean).
- Kaiser, P.K., 1980, Effect of stress-history on the deformation behaviour of underground openings, 13th Canadian Rock Mechanics Symposium, CIM Special Vol. 22, Montreal, 133-140.
- Kang, S.K., Yoon, J.S., 2008, The study on the predisplacement before face of the shallow tunnel in the weathered soil, Proceedings of the Annual Conference of the Korean Society for Railway, 947-954 (in Korean).
- KICT, 2003, Smart observation expert system, Final Report, Korea Institute of Construction Technology, 687p (in Korean).
- Kim, C.H., 2010, Forecasting final displacement with displacement functions using deformation measurements while constructing a tunnel, Tunnels and Underground Space, Korean Society for Rock Mechanics, Vol. 20, No. 6, 408-420 (in Korean).
- Kim, C.H., 2013, Relations between initial displacement rate and final displacement of arch settlement and convergence of a shallow tunnel, Tunnels and Underground Space, Korean Society for Rock Mechanics, Vol. 23, No.2, 110-119 (in Korean).
- Kim, C.H., Chae, Y.S., and Park, Y.J., 2008, Prediction of preceding displacements of a soil-tunnel by displacement monitoring using horizontal inclinometer, Tunnels and Underground Space, Korean Society for Rock Mechanics, Vol. 18, No. 5, 355-365 (in Korean).
- Kim, H.Y. and Park, E.S., 1993, Theory and analysis method of tunnel convergence, Tunnels and Underground Space, Korean Society for Rock Mechanics, Vol. 3, 80-95 (in Korean).
- Kim, K.Y., Kim, C.Y., Hong, S.W., Bae, G.J., Seo, Y.S., and Jeon, J.S., 2003, A study on the measurement of tunnel pre-displacement using horizontal inclinometer, Proceedings of the Annual Conference of the Korean Society of Civil Engineering, 4878-4883 (in Korean).
- Kitagawa, T., Kumeta, T., Ichizyo, T., Soga, S, and Sato, M., 1991, Application of convergence confinement analysis to the study of preceding displacement of a squeezing rock tunnel, Rock Mechanics and Rock Engineering, Vol. 24, No. 1, 31-51. https://doi.org/10.1007/BF01042717
- KR, 2008. Guidelines for the field measurements, Office for the Seoul Metropolitan Area, Korea Rail Network Authority, 61p (in Korean).
- Lombardi, G., 1979, Long-term measurements in underground opening and their interpretation with special consideration to the rheological behaviour of the rock, Field Measurements in Rock Mechanics, Zurich, Vol. 2, 839-858.
- MOCT (Ministry of Construction and Transportation), 2007, Design standard for tunnelling, Korean Tunnelling Association, 138p (in Korean).
- Otsuka, M. and Kondoh, T., 1981, On the displacement forecasting methods and their application to tunnelling by NATM, International Symposium on Weak Rock, Tokyo, 945-950.
- Panet, M. and Guenot, A., 1982, Analysis of convergence behind the face of a tunnel, Tunnelling '82, The Institution of Mining and Metallurgy, Brighton, 197-204.
- Park, S.H., 2008, A study on the application of the critical strain by using the displacements occurring before excavation in tunneling, Tunnels and Underground Space, Korean Society for Rock Mechanics, Vol. 10, No. 4, 337-347 (in Korean).
- Park, S.H. and Shin, Y.S., 2007, A study on the safety assessment technique of a tunnel using critical strain concept, Journal of the Korean Geotechnical Society, Vol. 23, No. 5, 29-41 (in Korean).
- Park, Y.H., 2011, Prediction of behavior during tunnel excavation using measured displacements Ph. D. thesis, Kyungpook National University, 236p (in Korean).
- Song, S.G., Yang, H.S., Lim, S.S., and Chung, S.K., 2002, Estimation of final deformation of hard rock tunnel using early measured deformation, Tunnels and Underground Space, Korean Society for Rock Mechanics, Vol. 12, No. 2, 99-106 (in Korean).
- Sulem, H., Panet, M. and Guenot, A., 1987, Closure analysis in deep tunnels, International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, Vol. 24, No. 3, 145-154.
- Vassilev, V.H. and Hrisstov, T.N., 1988, Influence of the heading face and a two-dimensional calculation model of tunnel linings, 6th International Conference on Numerical Methods in Geomechanics, Innsbruck, Vol. 3, 1551-1555.
- Yim, S.B., Yun, H.S., Seo, Y.S., and Park, S.H., 2007, Estimation of total displacements by RMR grades using 3-dimensional numerical analysis, The Journal of Engineering Geology, Vol. 17, No. 2, 217-224 (in Korean).