TY - GEN
T1 - Anisotropic closure analysis of a drift in Callovo-Oxfordian claystone based on in-situ convergence data
AU - Guayacán-Carrillo, L. M.
AU - Sulem, J.
AU - Seyedi, D.
AU - Ghabezloo, S.
AU - Noiret, A.
AU - Armand, G.
N1 - Publisher Copyright:
© 2015 by the Canadian Institute of Mining, Metallurgy & Petroleum and ISRM.
PY - 2015/1/1
Y1 - 2015/1/1
N2 - The main purpose of this paper is to analyze the convergence measurements in a drift excavated in the Callovo-Oxfordian claystone. The drift axis is in the direction of the major principal horizontal stress whereas the stress state is quasi-isotropic in the drift's section. The initial geometry of the drift being circular, the anisotropic character of the deformation is taken into account by assuming that the drift shape evolves in an elliptical shape. The convergence measurement data on six different points around the drift are analyzed to identify the main axes of the deformation ellipse, following the methodology proposed by Vu et al. (2013, Rock Mech Rock Eng, 46, 231-246). Then, using the semi-empirical law proposed by Sulem et al. (1987, Int J Rock Mech Min Sci, 24, 145-154), the convergence evolution is fitted independently for each axis of the ellipse. This method permits to distinguish two effects: the face advance effect and the time-dependent behavior of the ground. The results for the two directions of the ellipse axes show very close values for the parameters describing the time-dependent properties of the ground, the distance of influence of the face, and the extension of the decompressed zone around the gallery. Such model can provide valuable insights for predictions of the convergence evolution in the long-term.
AB - The main purpose of this paper is to analyze the convergence measurements in a drift excavated in the Callovo-Oxfordian claystone. The drift axis is in the direction of the major principal horizontal stress whereas the stress state is quasi-isotropic in the drift's section. The initial geometry of the drift being circular, the anisotropic character of the deformation is taken into account by assuming that the drift shape evolves in an elliptical shape. The convergence measurement data on six different points around the drift are analyzed to identify the main axes of the deformation ellipse, following the methodology proposed by Vu et al. (2013, Rock Mech Rock Eng, 46, 231-246). Then, using the semi-empirical law proposed by Sulem et al. (1987, Int J Rock Mech Min Sci, 24, 145-154), the convergence evolution is fitted independently for each axis of the ellipse. This method permits to distinguish two effects: the face advance effect and the time-dependent behavior of the ground. The results for the two directions of the ellipse axes show very close values for the parameters describing the time-dependent properties of the ground, the distance of influence of the face, and the extension of the decompressed zone around the gallery. Such model can provide valuable insights for predictions of the convergence evolution in the long-term.
KW - Anisotropy
KW - Claystone
KW - Convergence measurements
KW - Tunnel deformation
KW - Underground excavation
UR - https://www.scopus.com/pages/publications/85044108623
M3 - Conference contribution
AN - SCOPUS:85044108623
T3 - 13th ISRM International Congress of Rock Mechanics
BT - 13th ISRM International Congress of Rock Mechanics
A2 - Hassani, null
A2 - Hadjigeorgiou, null
A2 - Archibald, null
PB - International Society for Rock Mechanics
T2 - 13th ISRM International Congress of Rock Mechanics 2015
Y2 - 10 May 2015 through 13 May 2015
ER -