Minimum Weight Optimization of Offshore Jackets

Abstract

Offshore steel jackets are extensively used all over the world for the extraction of hydrocarbons from the reservoirs lying underneath the seabed. In this paper, the results of research carried out by the authors on the minimum weight optimization of the jacket for wave forces have been described. The gradient projection method has been used in the optimization. The jacket is modeled as a space truss and the cross-sectional areas of the tubular members have been the variables in the optimization process. The optimization histories with different sets of group area variables have been presented. The minimum weight design has been repeated over a range of ocean wave parameters, such as wave period, wave height, and wave direction, and the results are presented to indicate their interplay in the optimal picture.