| 摘要 |
A semi-submersible platform (11A-11D) is disclosed which includes a fully submersible lower hull (2) and a plurality of stabilizing columns (14) which extend from lower hull (2) to an upper hull (3). Each column has a dynamic wave zone (6) in the design seaway. At least one column (14) has means (20, 20a, 22, 27) adapted to reduce its water plane area (15) to a water plane area (15 min ) within a portion (7) of the dynamic wave zone (6) of the column and to increase the natural heave period (Tn) of the platform, so that the natural heave period becomes greater than the longest period of any wave with substantial energy in the design seaway, thereby lowering the platform's heave response. The means (20, 20a, 22, 27) is a channel which, in use, becomes flooded with sea water. |
