| 摘要 |
A semisubmersible offshore structure, e.g. for use as an offshore base to exploit and drill oil and/or gas reservoirs under the seabed or used as an offshore terminal to load, and unload cargoes, has buoyant column(s) or leg(s) 1 for supporting a topside provided with a constricted part 2 which is submerged even in the survival condition under bad weather. The constricted part is effective in suppressing wave forces. Either side of the part are tapered surfaces 3, 4 leading to wider cross-sectional areas. Alternatively, the wider parts are cylindrical or the constricted part is provided by recesses in the column. <IMAGE> |
