Reliability-Based Optimal Design of Steel Box Structures. II: Ship Structure Applications

Abstract

Traditional design of ship structures relies on a combination of experience, sound judgment, and deterministic approaches and typically ignores the potential for design improvement and other benefits offered through the use of reliability methods and structural optimization strategies. Part I of this article outlines the underlying theories involved in incorporating reliability methods and structural optimization strategies into the initial design of ship structures, whereas Part II (this paper) discusses their application to two case studies, namely, (1) a simple ship structure and (2) a more complex ship structure in an attempt to achieve weight reduction in the face of constraints on ultimate strength and buckling capacity. Using the approach outlined in the companion paper, a weight reduction of 5.6% was realized in the case of the simple vessel, whereas a 2.0% reduction was achieved in the case of the more complex vessel. A reduction in weight reduction has the potential to minimize the lifecycle cost, especially when including construction and operational and maintenance cost. These results highlight the potential benefits of reliability methods and structural optimization strategies, and encourage their implementation during the initial ship structural design phase.