Patent ID: 8899880

Claim:
A structure-assisted jackup system, comprising: a main deck structure; a plurality of legs movably coupled with the main deck structure, wherein during the initial assembly of the structure-assisted jackup system, the plurality of legs are lowered to the seabed so as to lift the main deck structure to a required elevation; a cantilever disposed upon the main deck structure; a derrick disposed upon the cantilever; wherein the main deck structure, the plurality of legs, the cantilever and the derrick form a jackup drilling unit; one or more support base structures disposed on seabed; and a plurality of movable supports, wherein each of the plurality of movable supports is securely coupled with the main deck structure; wherein during the assembly process of the structure-assisted jackup system the plurality of movable supports extend from the main deck structure to the one or more support base structures so as to allow the one or more support base structures to provide support for the weight of the main deck structure in replacement of one or more of the plurality of legs; wherein the one or more of the plurality of legs replaced by the one or more support base structures are designated as non-weight supporting legs, and the remaining of the plurality of legs not being replaced by the one or more support base structures as weight supporting legs; and wherein after the structure-assisted jackup system is assembled, the non-weight supporting legs are retracted into a position out of water, and the weight supporting legs together with the one or more support base structures via the moveable supports support the main deck structure.