Component of Structural Fixed Offshore Platform
In general, the main element of structural fixed offshore platform are presented in the following figure. By looking at its 2D view, it can be clearly seen that there are 4 decks which are available in Topside part. Wide Flange or Plate Girder profile is usually used as deck primary members. Using less section size, wide flange can also be designed for secondary members. Instead of wide flange, channel is another option of secondary member for supporting the integrity of structure. In the top of deck except helideck, plate or grating should be applied as acceptable movement access. In addition, grating is utilized in the top of Jacket Walkway and Boatlanding. Certainly, particular structure of helideck are supposed to be analyzed due to the chopper take-off/landing.
Tubular member with different diameters and wall thicknesses is generally selected for deck leg, deck vertical/diagonal bracing, jacket, pile, horizontal jacket framing, diagonal jacket bracing, and boatlanding. As protection purpose, Rubber should be placed at boatlanding member to absorb energy from ship/boat collision. So as to ensure the jacket on bottom stability, additional mudmate can be useful. It can be constructed by timber or steel properties. Another structural member that should be assembled are stair, ladder, and handrail. In spite of the fact that those members are neglected in performing structural analyses, weight assumption should be calculated as certain load consideration for engineering judgment.