Minimizing lifetime structural costs: Optimizing for production and maintenance under service life uncertainty

• The Pareto front between structural production cost and maintenace cost is developed.
• IFatigue, corrosion, and strength criteria under uncertain service life are included.
• A nominal naval destroyer-type vessel midship section is used as a case study.
• A Pareto front with a sharp knee is found, demonstrating the value of the framework.
• Service life uncertainty is shown to be significant in selecting optimal designs.

Current naval shipowners are being forced to extend the service lives of their aging vessels from budgetary and political constraints. This is causing them to incur significant costs due to maintaining the structure of these older ships to keep the ships in operation. These increasing costs make it desirable to design new naval structures with their minimization in mind, as well as ensuring that such vessels are robust to changes in expected service life with respect to their total lifetime cost. However, such structures will necessarily have higher production costs, therefore, an optimization framework is presented to estimate both production and maintenance costs for a naval vessel's internal structure and develop trade-spaces between these two competing objectives in order to find designs that represent a balance of both.