... circular tunnel gradient coefficient Rock Mechanics for Natural Resources and Infrastructure Development Fontoura, Rocca & Pavón Mendoza (Eds) © 2020 ISRM, ISBN 978-0-367-42284-4 Circular tunnel in a gradient elastoplastic rock mass G. Efremidis Department of Civil Engineering, University of Thessaly...

.... By realizing the definite value of horizontal and vertical translation, rotation, uniform compression/expansion, elliptic deformation, triangular deformation…etc. for a tunnel displacement, one can distinguish tunnel displacement and deformation types from their modal composition. A circular tunnel...

... ABSTRACT This paper presents an analytical closed-form elasto-plastic solution for displacement around a circular tunnel. The solution is based on strain-related parameters such as initial strain, strain boundary conditions and a strength criterion in termas strains. Engineering approaches...

... and radial displacement around a circular tunnel excavated in strain-softening Mohr-Coulomb rock masses is introduced. By assuming the initial stress is isotropic in the plane normal to the tunnel axis, the formulation is given on the plane strain condition. The finite difference approximation was carried...

... disturbance overburden sidewall Earthquake frequency Kobe oscillation dynamic behaviour Bantaki Tunnel tunnel Damage Pattern circular tunnel daikai underground station vertical oscillation 1257 Uenishi, K., Sakurai, S. The importance of incorporating dynamic effects of vertical oscillations...

... in tunnel design and construction. It has also been possible to verify that these expressions are similar to existing expressions obtained analytically for the case of a circular tunnel in a rock mass with homogeneous stress. The obtained expressions can be used to easily determine the expected...

... Upstream Oil & Gas criterion dilation longitudinal axial stress flow rule Reservoir Characterization axial stress reservoir geomechanics tunnel convergence axial stress 0 axial stress tr failure zone stress 0 rock mass tunnel circular tunnel displacement dilation parameter...

... ABSTRACT: The paper presents an analysis of stresses and ground response curves around a circular tunnel, introducing a seepage and using the Hoek-Brown failure criterion, a perfect elasto-brittle-plastic rock behaviour and a treatment of plastic strains according to an associated flow rule...

... des ungestuetzten Tunnels werden fuer die drei erwahnten Falle mitgeteilt. 1. INTRODUCTION Despite of the comparably simple geometry of a shallow circular tunnel, no general solution for the stress and strain fields above its roof is yet available. For the static conditions depend intricately...

... SUMMARY: By the use of integral equation method stresses and displacements around an advancing face of a circular tunnel are obtained for three fundamental cases; the axis of the tunnel is parallel and perpendicular, respectively, to the direction of uniform uni-directional initial pressure...

... will be made to the simple case of a circular tunnel driven in an homogeneous and isotropic medium; to satisfy axisymmetry, isotropic initial stresses will also be assumed. 1 - DEFORMATIONS CAUSED BY THE PROGRESS OF THE EXCAVATION - During excavation, deformations have a purely static cause. As the face...

... Summary: The effect of constructing tunnels in layered rocks as opposed to homogeneous rocks is discussed in this paper. The results represent solutions to plane strain boundary value problems using a finite element analysis. When a circular tunnel is excavated along a vertical contact between...