|Publisher||Offshore Technology Conference||Language||English|
|Content Type||Conference Paper|
|Title||Structural Design of the lceberg Resistant Hibernia Reinforced Concrete GBS|
|Authors||T.L. Huynh, Doris Development Canada Ltd; W. J. Clark, Morrison Hershfield Limited; D.C. Luther, Mobil Technology Company|
Offshore Technology Conference, 5 May-8 May 1997, Houston, Texas
|Copyright||1997. Offshore Technology Conference|
This paper deals with some of the unique and unusual aspects of the structural design of this GBS, which is the first offshore oil structure designed to resist iceberg forces, and will support a Topsides weighing 39000 tonnes at towout, increasing to 58000 tonnes in operation. There were significant challenges in developing a structural solution with adequate strength which was also constructible. In addition, unusual design situations resulted from the construction methods and the structural components used.
The Hibernia Oil Field is located 310 km south-east of St.John's, Newfoundland, on the Grand Banks, off the east coast of Canada. Recoverable oil reserves are estimated at 615 million barrels. The project is managed by a specially formed operating company, the Hibernia Management and Development Company (HMDC), on behalf of the partners of the Hibernia Field.
The main platform selected to develop the Hibernia reserves is a concrete gravity base structure (GBS), located in 80 m water depth. It is designed to include the following facilities and functions:
Predictably, the design of this first of its kind iceberg resistant structure, weighing approximately 450 000 tonnes, involved a large amount of structural analysis and detailing. Much of that work was challenging, and part of the challenge was to maintain constructibility.
It is not the intent of this paper to discuss the generalities of the structural design, but rather to deal with some of the unique and unusual aspects of that work.
lceberg Loads and Conceptual Development
The Hibernia GBS is the first offshore platform designed to withstand iceberg loads. This aspect dictates the basic structural form of the GBS (Figs. 1 and 2).
The iceberg data was provided by HMDC and included:
The basic steps of the methodology are as follows:
|File Size||594 KB||17|