Derived from the Italian word gabbione, a gabion is a container that is filled with sand or dirt. The device is often used in civil engineering projects, as well as some military applications and general road building. Gabions have been in use since medieval times, and are still employed by many civil engineers today.
In actual construction, the gabion is somewhat like a cage. The cage may be cylindrical or in the shape of a square or rectangular box. The cage may be constructed with a number of different materials, depending on the application. In some cases, the gabion is made with the use of metals, while gabions that are intended for temporary use may be composed of an outer shell of canvas or a similar material. Even wick has been used as the material of choice for a gabion.
One of the most common uses today for a gabion is to create a barrier that prevents erosion. Strategically constructing a retaining wall to prevent silt and topsoil from washing away during heavy rains or even floods can preserve land for crops as well as secure land for the use of buildings, airstrips, and other functions. Often, these types of gabions are made of metal or other materials that will not break down in the short term.
In a similar manner, a gabion may be used to construct a temporary flood wall. Stacking the gabions can help save buildings from flood damage and allow time for the waters to recede once the disaster is brought under control. Because the collection of gabions is temporary, they can easily be removed once the crisis is past. Often a qualified civil engineer will oversee the installation and removal of the gabion wall.
In times past, the gabion was also a means of protecting troops in the field of battle. Gabion cages made from wicker and filled with sand provided quick barriers and structures that would protect artillery from the arrows and projectiles of the enemy. These types of military fortifications could be assembled in a short period of time, and also broken down for a quick advance if necessary.