Caisson (engineering)

Rigid structure to provide workers with a dry working environment below water level

In geotechnical engineering, a caisson (borrowed from French caisson 'box', from Italian cassone 'large box', an augmentative of cassa) is a watertight retaining structure. It is used, for example, to work on the foundations of a bridge pier, for the construction of a concrete dam, or for the repair of ships. Caissons are constructed in such a way that the water can be pumped out, keeping the work environment dry.

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