Abstract
This work deals with reliability-based design and optimization of ship structures subjected to stochastic loads and accounting for the local fatigue damage and ultimate global strength. The reliability multi-objective structural optimization is performed in minimizing the structural component net-section area, lateral deflection and fatigue damage. The probability of compressive collapse and fatigue damage of the ship hull is used to define the minimum risk of structural collapse and best design solution. The Pareto frontier solutions calculated by the Non-Dominated Sorting Genetic Algorithm (NSGA-II) is employed in defining the feasible solutions of the design variables. The first order reliability method is employed to estimate the beta reliability index based on the topology of the structural component as a part of the Pareto frontier solutions. Comparing with the original design solution, the optimized section area decreased by 9%.