A tunnel favors communication.
Tunnel is a concept that comes from the English word tunnel . It is an underground route that is generally opened artificially with the aim of allowing communication between two places. In some cases, tunnels are created by nature.
For example: “The provincial government is building a tunnel on the hill to facilitate access to the town of Pucalpé” , “They should improve the tunnel signage to avoid accidents” , “One of the most important projects for the coming years is the construction of a subfluvial tunnel that links both provinces.”
Use of a tunnel
Tunnels make it possible to transport goods and people, although their characteristics are varied. There are tunnels only suitable for pedestrians, others that allow the passage of cyclists and some enabled for motor vehicles (such as cars, trucks, etc.). There are even tunnels designed especially for the passage of trains .
Tunnels are sometimes built in undeveloped natural terrain to improve communication . A tunnel, in this sense, can be built in a mountain to facilitate the passage of vehicles without the need for them to go around the elevation or have to climb its surface. The development of the tunnel, of course, requires an exhaustive study to analyze its viability .
In cities , tunnels are used to bury railways or for underground transport services such as the subway, to name two possibilities.
The tunnels are underground routes.
Its construction
There is a construction method called false tunnel used in works that begin by excavating the surface of all or almost all of the space that will be used for the tunnel, to carry out the open-air construction and then cover it once completed. In this case, it is necessary to have a system capable of supporting the structure and its respective loads.
It is possible to distinguish between two variations of this method, depending on the order in which the works are carried out:
- Bottom up : as stated above, the first step is to excavate to reveal the extension that the tunnel will occupy. Then we proceed with the interior works , manufacturing the concrete there or bringing prestressed concrete, arches with corrugated or prestressed steel, or brick (the most common material for the first false tunnels).
- Top down : unlike the previous method, this consists of digging a trench and concreting it from the surface to build the tunnel walls, and continuing with the upper slab once these have been completed. In this way, only the necessary hole must be excavated to mount the slab on the walls . Finally, the surface must be rebuilt, even before all the interior work is finished.
It is worth mentioning that the top down method is currently the most used to build tunnels in urban areas . Among its advantages over the other is the fact that it does not require the use of specialized machines. On the other hand, it also allows the creation of tunnels with more than one floor, through the use of intermediate slabs.
Tunnel making machines
To automate the tunnel creation process , tunnel boring machines are used, which have associated forward and backward systems .
There are many types of tunnel boring machines, and each of them adapts to a different type of work and the conditions of the work site (for example, the soil can be disintegrated or dense rock, among other possibilities, and this brings various challenges) .
The term in football
If we focus on football , finally, the play that consists of passing the ball through the opponent's legs is known as a tunnel , pipe or cassock .
The tunnel is usually very celebrated. It is considered a demonstration of skill by the player who manages to do it.