Comparative Study of Braced Monopod and Tripod Jacket Offshore Platforms

Abstract

Safety and economic aspects become the most important issues in the oil and gas industry. Therefore, the exploitation process of oil and gas does not only require a safe structure but also a highly efficient structure especially for a marginal field. Today, jacket fixed offshore platform becomes the main choice as one of important facilities in the exploitation process. In this paper, structural design and reliability analysis based on collapse failure mode for three (3) different types of offshore fixed platforms, they are braced monopod and tripod jacket with one (1) vertical leg, and tripod jacket without vertical leg are conducted based on API RP2A WSD. In this study, it is found that for the same loading conditions, braced monopod is more efficient than the tripod jacket with respect to material used, installation cost, and also has lower probability of failure. From sensitivity analysis due to soil capacity, it is shown that the structure with no vertical piles has better performance than the structure with vertical piles.