Browse > Article
http://dx.doi.org/10.9711/KTAJ.2016.18.2.235

Assessment of elastic-wave propagation characteristics in grouting-improved rock mass around subsea tunnels  

Kim, Ji-Won (KAIST, Dept. of Civil and Environmental Engineering)
Hong, Eun-Soo (KAIST, Dept. of Civil and Environmental Engineering)
Cho, Gye-Chun (KAIST, Dept. of Civil and Environmental Engineering)
Publication Information
Journal of Korean Tunnelling and Underground Space Association / v.18, no.2, 2016 , pp. 235-244 More about this Journal
Abstract
Grouting is frequently used before the construction of subsea tunnels to mitigate problems that can occur in weak ground zones such as joints, faults or unconsolidated settlements during construction. The grout material injected into rock mass often flows through the discontinuities present in the host rock and hence, joint properties such as its distribution, roughness and thickness greatly affect the properties of grouting-improved rocks. The grouting-improved zones near subsea tunnels are also subjected to high water pressures that can cause long-term weathering in the form of changes in grout microstructure and crack formation and lead to subsequent changes in ground properties. Therefore, an assessment method is needed to accurately measure changes in the grouting-improved zones near subsea tunnels. In this study, the elastic wave propagation characteristics in grouting-improved rocks were tested for various axial stress levels, curing time, joint roughness and thickness conditions under laboratory conditions and the results were compared with wave velocity standards in different Korean rock mass classification systems to provide a basis for inferring improvement in grouted rock-mass.
Keywords
Grout; Rock grouting; Elastic wave surveying; Subsea tunnel;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
연도 인용수 순위
1 Barton, N. (2007), Rock quality, seismic velocity, attenuation and anisotropy, CRC press, London, pp. 170-177.
2 Boadu, F.K. (1997), "Fractured rock mass characterization parameters and seismic properties: Analytical studies", Journal of Applied Geophysics, Vol. 36, pp. 1-19.
3 Brillouin, L., (1946), Wave Propagation in Periodic Media, Dover, New York.
4 Cha, M., Cho, G.C., Santamarina, J.C. (2009), "Long-wavelength P-wave and S-wave propagation in jointed rock masses", Geophysics, Vol. 74, No. 5, E205-E214.   DOI
5 Cho, M.R., Kang, T.H. (2003), "Application of the SASW method to the evaluation of grouting performance for a soft ground of a tunnel", Journal of the Korean Geotechnical Society, Vol. 19, No. 6, pp. 273-283.
6 Chun, B.S., Kim, D.Y., Lee, Y.N. (2002), "Shear characteristic of the cement grouted sawtoothed joints", Journal of the Korean Society of Civil Engineers, Vol. 22, No. 5-C, pp. 469-478.
7 Chun, B.S., Choi, J.K. (2003), "A study on the reinforcement of rock faults by grouting", Korean Geo-Environmental Society, Vol. 4, No. 4, pp. 45-51.
8 Dahlo, T.S., Nilsen, B. (1994), "Stability and rock cover of hard rock subsea tunnels", Tunnelling and Underground Space Technology, Vol. 9, No. 2, pp. 151-158.   DOI
9 Fratta, D., Santamarina, J. (2002), "Shear wave propagation in jointed rock: State of stress", Geotechnique, Vol. 52, No. 7, pp. 495-505.   DOI
10 Goodman, R.E. (1989), Introduction to Rock Mechanics, Vol. 2, Wiley, New York.
11 Holzhauser, J., Hunt, S., Mayer, C. (2006), "Global Experience with Soft Ground and Weak Rock Tunneling under Very High Groundwater Heads", Paper presented at the Proc. of the North American Tunneling Conference in Chicago.
12 Hwang, Y.C., Kim, N.Y., You, B.O., Kim, S.H., Choi, Y.K. (2000), "Evaluation of Grouting Effects using FRP Pipe in Soil Slope", Korean Society of Civil Engineers, No. 2, pp. 571-574.
13 Kim, M.G., Lee, Y.S. (2008), "A suggestion of a new rock mass classification system", Journal of the Korean Geotechnical Society, Vol. 24, No. 11, pp. 43-53.
14 Lee, J.S., Bang, C.S., Mok, Y.J., Joh, S.H. (1999), "Verification of the grouting effect using seismic tests and back analysis", Journal of the Korean Society of Civil Engineers, Vol. 19, No. 3-6, pp. 1135-1142.
15 Pariseau, W.G. (2011), Design Analysis in Rock Mechanics, Second Edition, CRC Press, London, pp. 507-511.
16 Pyrak-Nolte, L.U., Myer, L.R., Cook, N.G. (1990a) "Transmission of seismic wave across single natural fracture" Journal of Geophysical Research, Vol. 95, pp. 8617-8638.   DOI
17 Pyrak-Nolte, L.U., Myer, L.R., Cook, N.G. (1990b) "Anisotropy in seismic velocities and amplitudes from multiple parallel fractures" Journal of Geophysical Research, Vol. 95, pp. 11345-11358.   DOI