is type of land-based foundation
, invented by John Wellborn Root
, that protects against settlement and the liquefaction
of soft soil due to seismic activity. It was a necessary innovation in the development of tall buildings
in the wet soil of Chicago
in the 19th century.
For a floating raft foundation, or floating foundation, the foundation has a volume such that were that volume filled with soil, it would be equal in weight to the total weight of the structure.