What is Caisson?
and Caisson is a structure used in construction and engineering, especially underwater projects such as the bridge or the construction of the dam. Its purpose is to provide a dry, protected environment for workers and building materials. While the water is kept outside the structure, the air is allowed inward to remove the need for diving equipment and the like. This structure has been used in construction since the 18th century. The structure keeps water outside the building area, while its open bottom allows workers to place foundations and pier in the seabed or river wheels. An open shrub is used in shallow water; Its open upper part allows you to enter light and air out of the playing water. For the construction of deep water, the pneumatic Caisson has a closed top; The pressure air is pumped in and the staff enters and leaves through the air air. Both types have a sharply tilted lower edge, allowing the deep structure built into the ground so that the water can not penetrate. The engineers prefer the subsoil layer below it. If PThey postpone too far below the ground, sometimes rely on the affected mud or the ground, or create an artificial foundation.
with pneumatic kesons, mud, rock and other undesirable materials are brought to the surface through the "Muck" tube, which connects to the upper part of Caisson. Cranes on the surface move this material from the construction site. The mud tube also helps to stabilize the air pressure by releasing excess air. Upon completion of the structure in the structure, the structure can be moved to allow the work to continue in another place.
Thecisas were used in the construction of early American bridges, such as the Eads bridge in St. Louis, Missouri and Thebrooklyn Bridge in New York. Many workers, including head engineer Brooklyn Bridge Washington Roebling, suffered from what was called Caisson's disease at the time; Some have died. This disease was later found as a decompression disease caused by the inability of humanadapt to rapid changes in external pressure. Modern employees compensate for this by gradually returning to the surface, as well as the deep sea divers.
The term Caisson is also used to indicate various other engineering and architectural structures. The Caisson Foundation can be anchored deep underground in the non-exhibition. During transport, during passages, such as channels, filled with water for water, transport from one height to another. In architecture, the Caisson structure is similar to a box used in the construction of a dome or ceilings and sometimes called a cassette.
The military definition of Caisson also includes a box that carries ammunition during battle and coffin during a military funeral. Although it differs from the type of engineering, all these devices share a similar shape.