Tunneling route

However, another possibility can be drawn, which is the fact that in the absence of cytochrome c, a second tunneling route appears via flavodehydrogenase. This route could be inhibited In the presence of cytochrome bj and will be reactivated in its absence. 

If the tunnelling mechanism provides the only predissociative pathway, the isotopic sensitivity should be greatest when v = 0, since this would correspond to the maximum barrier width. In fact, the rates of predissociation from levels with v = 0 in HCN and DCN, as reflected by the observed line widths, polarization ratios and relative CN(5) quantum yields, are very similar, and an alternative pathway must still be available when the tunnelling route is too slow to compete i.e. when ui = 0 in HCN and when ui < 2 in DCN,... 

Fig. 39.7 Navigation view of the knee. Virtual tunnel routes are shown as green columns on the three- or two-dimensional (3D or 2D) model, (a) The 3D image is rotated 90° on the navigation screen in order to evaluate the risk of a back wall blowout. The total length of the femoral tunnel can be evaluated at the same time (red circle).

Occurrence of deformed and crushed rock mass along tunnel route poses several hindrances during excavation like formation of cavities, collapses, debris flow etc. Encountering such zones during excavation is common. 

Predicting the occurrence of mixed face conditions in tunnel route of Line 2 Tabriz metro, Tabriz, Iran... 

By designation of engineering geological profiles of tunnel route, according to Geological and Geotechnical studies, the sections having mixed face potential are determined. 

In this study. Possibility of this phenomenon in the tunnel route of Line 2 Tabriz metro is discussed. The tunnel route is mostly located on alluvial sediments and moderately cemented sedimentary rocks. With this variety of lithological units, occurrence of mixed face in some sections of the tunnel is probable. 

M2 Alternation of greengray and red marl with Intercalation of gypsiferous and saltlferous sandy marl. Tunnel Route... 

Figure 3. Geological characteristics of Tabriz city and tunnel route.

ENGINEERING GEOLOGICAL CHARACTERISTICS OF TUNNEL ROUTE AND POSSIBILITY OF MIXED FACE OCCURRENCE... 

Geological and Geotechnical properties of tunnel route have discussed previously. In this part, an investigation on the soil behavior against TBM excavation is presented. 

Section 2 is located at chainage Km 9 + 500 and have a similar situation to section 1. In this part of tunnel route, the position of the Ground Water Table (G.W.T) relative to the tunnel crown can cause to different behaviors of materials in above and underground water table. 

Engineering geological properties of the Tabriz urban railway line 2 (TURL2) tunnel were discussed in this study. The materials of the tunnel route mostly consist of quaternary alluvium and Miocene formations that lithologically composed of sandstone, siltstone, claystone and marl. The status of these geological units is similar to soil (stiff soil at lower depths) layers that have different Geotechnical characteristics so it is expected that each of layers show a specific behavior during excavation. 

Since 2005 the condition surveys on 8 tunnel routes of St. Petersburg Metro, located in different parts... 

Piarc Ita 2004 Fire Safety in Tunnels. Routes-Roads. World Road Association (PIARC) International Tunnelling Association (ITA). 

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