The boundary element technique is a practical problem-solving tool and useful in comparison to other currently popular alternatives. In this paper, a circular tunnel of a diameter 3.4 m is to be excavated through a clayey soil and surrounded by concrete lining of a thickness 0.2 m, so the clear internal diameter is 3.0 m. A plane strain analysis is adopted for such problem and the soil is assum...

nowadays deep excavations are needed for construction of foundation of high rise buildings, providing space for parking and etc. in some cases deep excavations may be constructed in the vicinity of the subway tunnels and causes unpredicted extra displacements and internal forces in tunnel lining of tunnels which were not designed for them and consequently affect serviceability of tunnel. theref...

Displacements around a tunnel, occurring as a result of excavation, consist of the elastic and plastic parts. In this paper, we discuss the elastic part of displacements as a result of excavation, called net displacement. In general, the previous analytical solutions presented for determining the displacements around a circular tunnel in an elastic medium do not give the net displacements...

Nowadays deep excavations are needed for construction of foundation of high rise buildings, providing space for parking and etc. In some cases deep excavations may be constructed in the vicinity of the subway tunnels and causes unpredicted extra displacements and internal forces in tunnel lining of tunnels which were not designed for them and consequently affect serviceability of tunnel. Theref...

Dimensionless coefficient () in convergence confinement method shows the relaxation of stress in the wall of the tunnel at different excavation movements. This factor is considered a constant number in previous studies and tunnel geometric characteristics (such as depth, cross-section shape, radius, soil material, etc.) are not included in its determination; however, ignoring these effects can...

wall displacements and ground pressure acting on the lining of a tunnel increase with time. these time-dependent deformations are both due to face advance effect and to the time-dependent behavior of the rock mass.  viscoelastic materials exhibit both viscous and elastic behaviors. thorough this study, the effect of different linear viscoelastic models including maxwell, kelvin and kelvin-voigt...

Wall displacements and ground pressure acting on the lining of a tunnel increase with time. These time-dependent deformations are both due to face advance effect and to the time-dependent behavior of the rock mass.  Viscoelastic materials exhibit both viscous and elastic behaviors. Thorough this study, the effect of different linear viscoelastic models including Maxwell, Kelvin and Kelvin-Voigt...

The TolC channel-tunnel spans the bacterial outer membrane and periplasm, providing a large exit duct for protein export and multidrug efflux when recruited by substrate-engaged inner membrane complexes. The sole constriction in the single pore of the homotrimeric TolC is the periplasmic tunnel entrance, which in its resting configuration is closed by dense packing of the 12 tunnel-forming alph...

this paper addresses the problem of quantifying the mechanical contribution of rockbolts installed systematically around tunnels (regularly spaced around the tunnel) excavated in rock masses. assuming that the mechanical contribution of grouted rockbolts is that of increasing internal pressure within a broken rock mass, a new procedure for computation of ground response curves for a circular tu...