Definition

Noun: A pneumatic caisson is a large, watertight, pressurized chamber used in construction to allow workers to perform tasks in a dry environment below water level or in waterlogged ground. It is a type of foundation engineering structure.

Usage

The term is used in civil engineering, construction, and architectural contexts to describe a specific method for building foundations, bridge piers, or other structures in wet conditions. - It is a technical, compound noun. The word "pneumatic" refers to the use of compressed air to keep water out of the working chamber. - It is typically used in its full form, "pneumatic caisson."

Examples

Advanced Usage

• The concept is often discussed in relation to historical engineering projects (e.g., the Brooklyn Bridge, the Eads Bridge) and in modern geotechnical engineering.
• The pressurized environment inside the caisson can pose health risks, such as decompression sickness ("the bends"), leading to the term caisson disease.

Variants and Related Words

• Caisson: A more general term for a watertight structure used in construction. A pneumatic caisson is a specific type of caisson.
• Open caisson: A caisson that is open at the top and bottom, which is sunk into place and then filled with concrete.
• Box caisson: A prefabricated watertight box that is floated to the site and sunk onto a prepared base.
• Caisson disease: A medical condition caused by rapid decompression, historically associated with workers in pneumatic caissons.

Synonyms

• Compressed-air caisson
• Pressurized caisson

Notes

• This is a highly specialized technical term. In general language, the simpler term "caisson" may be used, but "pneumatic caisson" specifies the use of compressed air.
• It should not be confused with a caisson in military contexts (an ammunition wagon) or in artistic contexts (a sunken panel in a ceiling).

Noun

1. large watertight chamber used for construction under water