open caisson

construction

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Last updated

July 16, 2026

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An open caisson is a boxlike structure used in underwater construction and foundations. It is open at both the top and bottom and features a cutting edge at its base, which aids in sinking through soft materials. Excavation occurs inside the caisson through large pipes or dredging wells. As the caisson sinks, additional sections are added to the shaft above. Once it reaches the desired depth, a concrete floor is laid to create a seal, and the wells are filled with concrete to complete the structure. This method is employed for foundations of structures like piers, seawalls, and breakwaters. Merriam-Webster defines it as a small cofferdam that is set in place, pumped dry, and filled with concrete to form a foundation.12

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caisson
An open caisson, open at both the bottom and the top, is fitted with a cutting bottom edge, which facilitates sinking through soft material while excavation is carried out inside through a honeycomb of large pipes, or dredging wells. As excavating proceeds and the caisson sinks,…
Read More
An open caisson, open at both the bottom and the top, is fitted with a cutting bottom edge, which facilitates sinking through soft material while excavation is carried out inside through a honeycomb of large pipes, or dredging wells. As excavating proceeds and the caisson sinks,…
Read More