Base tunnel: Difference between revisions

Content deleted Content added

Inline

Revision as of 16:56, 6 June 2016

A base tunnel is a type of tunnel (often but not always a railway tunnel) that is built through the base of a mountain pass.

When originally constructed the "classical" lines through mountainous terrain tried to minimize tunnelling, due to technical limitations and expense limits, often with the consequence of long and steeper gradients and many curves, or even spirals. Such tunnels are sometimes also called culmination tunnels, especially in the presence of a base tunnel through the same mountain massif.

The base tunnels take the opposite approach, eliminating, or at least, minimizing gradients and eliminating curves with the consequence of having longer tunnels, but shorter distances to travel. Usually, there is an already existing culmination tunnel, and it would not be possible or reasonable to build a tunnel at an even lower altitude.

Base tunnels include:

Gotthard Base Tunnel, Switzerland
Zimmerberg Base Tunnel, Switzerland
Brenner Base Tunnel, Austria and Italy
Furka Base Tunnel, Switzerland
Ceneri Base Tunnel, Switzerland
Lötschberg Base Tunnel, Switzerland
Apennine Base Tunnel, Italy
Mont d'Ambin Base Tunnel, France and Italy
Pajares Base Tunnel, Spain
Semmering Base Tunnel, Austria

@@ Line 3: / Line 3: @@
 A '''base tunnel''' is a type of [[tunnel]] (often but not always a railway tunnel) that is built through the base of a mountain pass.
-When originally constructed the "classical" lines through mountainous terrain tried to minimise tunneling, due to technical limitations and expense limits, often with the consequence of long and steeper gradients and many curves, or even spirals. Such tunnels are sometimes also called [[culmination tunnel]]s, especially in the presence of a base tunnel through the same mountain massif.
+When originally constructed the "classical" lines through mountainous terrain tried to minimize tunnelling, due to technical limitations and expense limits, often with the consequence of long and steeper gradients and many curves, or even spirals. Such tunnels are sometimes also called [[culmination tunnel]]s, especially in the presence of a base tunnel through the same mountain massif.
-The base tunnels take the opposite approach, eliminating, or at least, minimising gradients to a minimum and eliminating curves with the consequence of having longer tunnels, but less longer distances to travel. Usually, there is, first of all, an already existing culmination tunnel, secondly, there would not be the possibility or reasonability to built a tunnel at an even lower altitude.
+The base tunnels take the opposite approach, eliminating, or at least, minimizing gradients and eliminating curves with the consequence of having longer tunnels, but shorter distances to travel. Usually, there is an already existing culmination tunnel, and it would not be possible or reasonable to build a tunnel at an even lower altitude.
 Base tunnels include: