Development of Reliability-Based Damage-Tolerant Optimal Design of Ship Structures

Abstract

While in service, ship structures are continuously subjected to environmental loading and deterioration, which could lead to increased inspection and maintenance costs during a vessel’s lifecycle. The design strategy presented in this study considers structural damage, such as corrosion and fatigue, and makes some provision for their impact on structural integrity. If adopted during the conception and design stage, such a strategy could lead to a reduction in lifecycle costs. The approach synergistically combines advanced computational methods, damage models, probabilistic tools, and optimization techniques to enhance the robustness and overall structural reliability of ship structures. The study first presents a formulation of system reliability-based damage-tolerant optimal design models. The design strategy is illustrated through an example problem involving the redesign of a tanker structure for optimal performance and reliability. The sensitivity of the optimal design to uncertain design parameters, such as material properties and loads, is also investigated.