Optimization Study of Eight-Legged Fixed Offshore Jacket Platform

Abstract

Fixed offshore platform plays a major role in oil exploration and production and basically, a huge steel-framed structure used for different purposes such as drilling, processing and living. The quantity of steel required to meet the extreme environment of the ocean will be comparatively high and by using modern techniques and developments, researchers and consultants are trying to adopt the innovative methods to optimize the weight of the jackets. In this paper, a typical eight-legged jacket platform is taken for study and optimization is carried out by concentrating in various aspects such as leg batter, rechecking the member size requirements, bracing arrangement, utilization of FRP mud mats, rechecking the load calculations and contingency factors. The modelling, analysis and design are done using SACS, a 3D finite element software exclusively for offshore structures. Generally, during the tender stage of the projects, and due to the time constraint, many possible checks shall not be done especially for optimization. Being a contractor’s consultant, it is the consultant’s responsibility to provide economical design. This study will provide the fair idea about the possible routes for the optimization. This paper concludes with the final optimum weight of the jacket platform and highlighting the spaces where the weight of the jacket structure can be reduced. The percentage of reduction is summarized in the conclusion for the comparison purpose.