Abstract: A hydraulic lift caisson for buildings including an outer rigid pipe, an inner rigid lifting post and a plurality of threaded lifting rods surrounding the inner rigid lifting post. Also included is a base lifting plate disposed within a bottom end of the outer rigid pipe and connected to a bottom end of the inner rigid lifting post and threaded rods, an anchor plate fixed to a first end of the inner rigid pipe and including a plurality of holes extending therethrough to receive the threaded lifting rods therethrough and a jacking plate disposed above the anchor plate and also including a plurality of holes extending therethrough to receive the threaded lifting rods therethrough, and at least one hydraulic jack disposed between the anchor plate and a jacking plate to lift the jacking plate, lifting post and building.

Abstract: A caisson for use as a support structure in building construction. The caisson has an inner, metallic core and an outer portion surrounding the inner core. Both the inner core and the outer portion are cylindrical. Metallic straps or bands can be disposed peripherally, in spaced apart relation, around the inner core for anchoring it to the outer portion of the caisson. The inner, metallic core is usually steel and the outer portion is concrete or grout. A 22″ diameter caisson manufactured in accordance with this invention is capable of supporting more than 2,400 tons. A hollow, cylindrical, steel shell optionally surrounds the outer periphery of the outer portion of the caisson.