Tunnels connect worlds
Who invented them? The Swiss! This idea about railway tunnels may be obvious, but it is not true.
With several large tunnel projects in the country, some of which have already been completed – the Gotthard Base Tunnel, the world’s longest railway tunnel – and others still under construction, Switzerland has certainly set standards. But, as a matter of fact, the first railway tunnel was put into operation as early as in 1836 in the then Prussian province of Saxony on the Tollwitz-Dürrenberg railway, with a track gauge of 585 millimetres. As in the past, tunnel constructions are still considered special challenges in terms of building technology. The work is difficult, not only because of geological peculiarities with unexpected surprises during construction but also due to the often difficult boundary conditions for access to the construction sites and the supply of the required materials.
Not to forget – gigantic tunnel boring machines with diameters of several metres are required for the mechanical boring of the tunnel tubes. A company founded in 1977 in the small town of Schwanau in southwest Germany has shown a pioneering spirit and set standards in this field: Herrenknecht AG.
Four ladies set the rhythm
‘Stuttgart 21’ and its associated projects are expected to change a lot in rail transport in Germany and the neighbouring countries. A difficult terrain and various tunnels are part of the Stuttgart – Ulm rail project which is divided into the major project ‘Stuttgart 21’ and the new Wendlingen – Ulm line. All the machine-bored tunnels could be rapidly drilled within just five years. Suse, Sibylle, Wanda and Käthchen, the names of the EBP shield tunnel boring machines from Herrenknecht AG in Schwanau, traditionally bearing women’s names, were largely responsible for this achievement. As a result, the approximately 50 kilometres of the key tunnel structures Filder, Albvorland and Bossler are now ready for the next construction steps. Suse, a convertible multi-mode tunnel boring machine with a diameter of 10,820 millimetres, was used in the Filder tunnel near Stuttgart, while Sibylle and Wanda, two identical EBP shield machines, both with a diameter of 10,820 millimetres as well, were used in the Albvorland tunnel, coming from the south and north respectively. In the Bossler tunnel, the EBP shield machine Käthchen with a diameter of 11,340 millimetres worked its way about 8.8 kilometres to reach the target.
Herrenknecht tunnel boring machines were and are in use all over the world. Among other things in the construction of the Eurasia Tunnel which connects Europe with Asia through the Bosporus, in the Gotthard base tunnel as the world’s longest railway tunnel or in Doha (Qatar), where 21 shield boring machines were used simultaneously to build the metro.
But before railway tunnels can connect cities and countries, as in the planned Fehmarn Belt Tunnel, or even continents, a large number of details in planning, construction and technical equipment have to be taken into account in addition to knowledge and experience.
Herrenknecht Hall 5.2 | 820