Reliability-based multi-objective optimization of offshore jacket structures

In the light of the ever-growing requirements in ecological concerns, government legislations, and consumer demanding, this paper focuses on the structural design of lightweight offshore structures with acceptable levels of reliability. The conflict in these two parameter figures a multi-objective problem with minimizing jacket mass and maximizing reliability as objective functions with member group dimensions as design variables. A Multi-Objective Particle Swarm Optimization (MOPSO) algorithm is selected to solve the problem to obtain the Pareto optimal frontier. The Radial Basis Function (RBF) coupled with Monte Carlo Simulation (MCS) is used to approximate the response of objectives and evaluate reliability in the context of optimization. The study aims to provide multiple solutions for the structural design considering economic cost and structural integrity. Although a Pareto frontier provides multiple solutions, we use the knee point by minimum distance method to decide the most acceptable arrangement from Pareto set.