Method and apparatus for piled foundation improvement with freezing using down-hole refrigeration units

Abstract

The invention relates to a method and apparatus for increasing the capacity of a tubular driven pile. A refrigeration unit is lowered into the pile and grouted in place above a cement plug. The area between the refrigeration unit and the plug is filled with a secondary refrigerant. Seawater fills the pile above the refrigeration unit and is used for refrigeration unit cooling. The refrigeration unit cools the brine until the soil surrounding the pile is frozen. The adfreeze strength of the frozen soil and the pile increase the pullout resistance of the pile. Further, the end-bearing capacity of the pile is increased as a result of the large frozen mass surrounding the pile.

Dependencies are inferred from the claim text.