Designing sustainable ocean infrastructure using reliability based design optimization: a case study of three-legged jacket offshore platform

Abstract

Infrastructure is essential in utilizing maritime resources and requires reliability, resilience, and cost-effectiveness. In the design phase, recent developments in computational approaches have led to design optimization that relies more on science than on the engineering judgment of designers. However, the final result of design optimization is sometimes impractical and has a lower expected lifetime due to drastic reduction. Therefore, reliability is considered during the optimization process as part of the structural evaluation. The case study for this investigation was an offshore jacket platform with three legs. Within the context of the optimization process, reliability serves as a constraint. The goal is to bring down the overall weight of the structure. The tubular elements of the jacket construction are referred to as variables. Variables are separated into several different groupings. The results show that considering the reliability index does not reduce the weight of the structure as much as deterministic optimization. However, the structure’s reliability is not violated, and yet the structure is more economical and still reliable.