OFFSHORE CAISSON

摘要

1. An offshore structure for use in a body of water having a surface and a seafloor, said offshore structure comprising a tubular caisson structure having a lower foundation section and an upper section separated by a structural diaphragm, said lower foundation section extending downwardly from said seafloor into the seabed a distance to provide sufficient lateral and vertical soil resistance to resist lateral and vertical loads on said offshore structure, said upper section extending upwardly from said seafloor to a point above the surface of said body of water and adapted to support a deck structure on the upper end thereof, said structural diaphragm adapted to rest on the seafloor when said offshore structure has been fully installed to enhance the lateral and vertical load carrying capacity of said tubular caisson structure. 2. The offshore structure of Claim 1 further comprising means for creating suction in said lower foundation section during installation of said offshore structure to assist said tubular caisson structure in penetrating into said seafloor. 3. The offshore structure of Claim 1 wherein said structural diaphragm is a solid partition having at least one valve for allowing fluid to flow between said upper section and said lower foundation section of said tubular caisson structure and having a pump for forming the suction in said lower foundation section of said tubular caisson structure. 4. The offshore structure of Claim 3 wherein said pump is adapted to pump fluid out of said lower foundation section of said tubular caisson structure. 5. The offshore structure of Claim 1 wherein said upper section of said tubular caisson structure further comprises an ice resistor. 6. The offshore structure of Claim 1 wherein said tubular caisson structure is sized to house a plurality of well conductors. 7. The offshore structure of Claim 1 wherein said tubular caisson structure is formed of steel. 8. The offshore structure of Claim 1 wherein said tubular caisson structure is formed of concrete. 9. The offshore structure of Claim 1 wherein said tubular caisson structure is formed of a composite material. 10. The offshore structure of Claim 1 wherein said lower foundation section of said tubular caisson has a larger cross-sectional diameter than the cross-sectional diameter of said upper section of said tubular caisson structure. 11. The offshore structure of Claim 1 wherein said tubular caisson structure is a unitary structure. 12. The offshore structure of Claim 1 wherein said upper section and said lower foundation section of said tubular caisson structure are separate units that are mechanically connected. 13. The offshore structure of Claim 1 wherein said tubular caisson structure further comprises jets attached to the lower foundation section of said tubular caisson structure, said jets adapted to facilitate installation of said tubular caisson structure.