At present tunnels tend to be analyzed on the basis of 2D finite element computations , because 3D analyses are considered to be extremely time consuming. As a result, 3D analyses are presently the domain of researchers. Consulting engineers will only perform 3DFEM analyses when facing complex geometries, e.g. tunnel joints or connections to underground stations, but not for straight-ahead tunn...

The influence of anatomical or nonanatomical femoral tunnel position on tunnel widening and clinical outcomes in patients undergoing anterior cruciate ligament (ACL) reconstruction is not fully understood. This retrospective study examined the influence of tunnel width and placement on anterior knee stability and clinical outcomes after ACL reconstruction using the AperFix System (Cayenne Medic...

We present theoretical and experimental results on the effect of periodic perturbations on microwave-driven Josephson tunnel junctions close to a period-doubling bifurcation. The theory, which is quite general, describes how a periodic near-resonant perturbation changes the stability of the system. The phenomenon was investigated experimentally in small Nb-NbOx-Pb tunnel junctions and found to ...

the hydraulic pressure is one of the most important factors in the design of pressure intake tunnels. since the surrounding media cannot usually resist the high internal pressure of these tunnels, they are usually finished with an adequate lining mostly of reinforced concrete, which is an interaction problem between water, soil or rock and concrete lining. although reinforcing the concrete lini...

Having knowledge of stability of an underground space depends on stresses and strains around it. Creating underground tunnels leads to significant changes in the rock mass stress. Therefore, to achieve the necessary stability, stresses and deformations around the tunnel must be examined carefully. Usually, stress-strain behavior analysis is conducted in two-dimensional mode. This paper was cond...

For the two types of shield tunneling such as Slurry and EPB shield the stability of tunnel face depends on the prevailing support pressure. The support pressure at the tunnel face has to be applied to a value that gives as well sufficient safety against a collapse of the tunnel face as the against uplifting. The paper aims at a better understanding of the mechanics of face failure for those la...

The design of underground spaces is mainly carried out using empirical, analytical, and numerical methods. The convergence confinement method (CCM) is an analytical technique that is widely utilized in analyzing the stability of underground spaces. However, the main challenge in the stability analysis is the selection of an accurate constitutive model for rock mass, and particularly, its post-f...

This paper focuses on the face stability analysis of Double-O-Tube shield tunnel. This kind of analysis is significant to ensure the safety of workers and reduce the influence on the surrounding environment. The key point of the stability analysis is to determine the supporting pressure applied to the face by the shield. A collapse failure will occur when the supporting pressure is not sufficie...

The hydraulic pressure is one of the most important factors in the design of pressure intake tunnels. Since the surrounding media cannot usually resist the high internal pressure of these tunnels, they are usually finished with an adequate lining mostly of reinforced concrete, which is an interaction problem between water, soil or rock and concrete lining. Although reinforcing the concrete lini...

this paper presents the results of engineering geological studies of rock blocks along a road tunnel in nw iran. the tunnel is to cross the western alborz mountain range through 530 m in length with 11.2 m span and 8 m height. eocene tuffs and andesites crop out in whole of the tunnel route. numerical analyses are done using, a 3d stability analysis and visualization program, called unwedge tha...