Summary: | In the early seventies the hydrocarbon development of the Beaufort Sea - McKenzie delta region started with the search for oil. To determine if hydrocarbon reserves were to be found a number of artificial exploration-islands were designed and built between 1973 and 1986. Artificial islands were chosen to function as drilling platforms because the easy construction method and the high resistance against ice loads. From the different islands several oil discoveries were made and islands design was found to be sufficient for the exploration purpose. To anticipate future development of the offshore area of the Beaufort Sea when present reserves become depleted a study is made of the artificial island designs. A research is conducted in developing the designs from exploration islands to production facilities. In this thesis report a study is made of the artificial islands designs in the severe circumstances of the Beaufort Sea, the extreme climate posting special design considerations and construction techniques. In this research the question is stated: "Can exploration artificial island design be used as a design for permanent production islands in the extreme environment of the Beaufort Sea - McKenzie delta region?" Production islands have to function much longer and therefore have to withstand higher forces. Exploration designs were designed with a boundary condition of a ten-year return period, for production islands a return period of 100 years has to be taken into account. Complicating factor in the design is the absence of heavy armour layer materials to protect island slopes. Common protection methods for island slopes and other slopes are not available. Purpose of this thesis study is to determine what the maximal lifetime expectancy is of the artificial exploration island designs. Furthermore a number of production island considerations are studied and evaluated. To be able to give a correct overview of the islands that were built between 1973 and 1986 first a thorough literature study has been completed. ...
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