Patent ID: 6244785
Filing Date: 2001-06-12
Classification: B63B,E02B

Abstract:
A precast, modular spar system comprising:a. a cylindrical open-ended spar of relatively uniform cross section throughout its length and having a length such that its upper end extends above the water surface and its bottom end is subject to only minimal excitation forces caused by waves, said spar comprising a freeboard section, a buoyancy section, and a ballast section;b. a plurality of arcuate shaped segments having a middle tangential wall, at least two outer tangential walls, an outer radial wall, an inner radial wall, and a top slab; said segments adapted to be in a stacked relationship with an adjoining segment;c. said segments comprising said ballast section having a passageway extending through said top slab;d. an equalized pressure system for pressuring the spar throughout its length and to approximate the pressure of the sea water on the outside of the spar system, said equalized pressure system comprising a plurality of double walled equalized pressure pipes extending through said segments of said buoyancy section, a plurality of segmented water columns within said double walled pipes, means for injecting air into said segments;e. a moon pool open at the bottom and containing water non-excited by waves centrally extending the entire length of the spar and defined by inner radial walls of said sections.