Naval Ship Structure Service Life Considerations

This paper presents a framework for considering both risk and total ownership costs in the determination of the end of service life of ship structure. Modes of failure are discussed and differences noted between serviceability and ultimate capacity. Incorporation of time-dependent structural reliability is discussed. The trade-offs between risk and minimum total ownership costs are illustrated. The role of hull structural health monitoring in achieving minimum TOC is presented. An example is presented where estimated costs associated with structural damage repairs required to maintain serviceability exceeded available funding thus defining end of service life.