Gotthard Base Tunnel

In light of the new 57 km AlpTransit Gotthard base tunnel, which is currently under construction and whose trajectory passes close to several dams, the assessment of possible surface subsidence is of great interest. In this paper we present the results of a two-dimensional finite-element study which includes coupled fluid pressure diffusion and consolidation with the rock mass treated as an equivalent isotropic porous medium. 

At the Faido multifunction station of Gotthard base tunnel project (Ehrbar 2008), the cutterhead had been changed from 8.80 m to 9.40 m in order to obtain more space for deformations and rock support. The deformation behind the cutter head became locally big, and there was a risk that the back-up installation could not pass through the excavated hole. Due to very large radial deformations and an influence of the second tube on the first (eastern) tube, some heavy damage unexpectedly presented in the rock support and lifting of the concrete floor (see Fig. 3). 

Figure 4. Gripper TBM with shrinkable canopy used at Gotthard base tunnel (Herrenknecht 2009).

Ehrbar, H. 2008. Gotthard base tunnel, Switzerland experiences with different tunneling methods, International South American Tunnelling. 

Herrenknecht M, Bockh O, Bappler K. 2009. Gotthard Base Tunnel, Section Faido previous experience with the use of the TBM. Proceedings of the Rapid Excavation and Tunnelling Congress, Las Vegas 1182-1205. SEM Inc. Littleton. 

I The Gotthard Base Tunnel network is being built under the Alps from Switzerland to Milan, Italy. At about 35 miles, the two-way tunnel will be the longest in the world and will reduce the time to make the trip by automobile from 3.5 hours to 1 hour. High-speed trains traveling at speeds of 155 miles per hour will make more than two hundred trips through the tunnel per day. 

An example for such a situation is given by the new deep Alpine tunnels, which are being constructed in Switzerland. The AlpTransit (NEAT) project comprises two long deep (overburden up to 2.5 Ion) tunnels, the Gotthard and Lotschberg Base Tunnels, which drain substantial quantities of warm water from the... 

Switzerland presently follows the traffic policy of shifting transport by heavy trucks on roads to railway transport. Towards this goal, the capacity of the main traffic axis (N S) is now being greatly expanded by the AlpTransit project. The key elements of this project are the two railway base tunnels the Lotschberg tunnel in the west and the Gotthard tunnel in the east (see Fig. 7). The rock overburden can reach 2.5 km, and the lengths are considerable 57 km... 

Below I focus on three aspects first, on the lives of women and men, based on examples at the tunnel construction sites at the two portals of the historical Gotthard... 

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