Fracture Evaluation and Design Tool for Welded Aluminum Ship Structures Subjected to Impulsive Dynamic Loading

Aluminum as a structural material for naval applications has a number of advantages over steel, owing mainly to significant weight reductions which translate to higher speed and range attainable by aluminum vessels. A comprehensive study of research needs for aluminum structures conducted under the ONR program identified the key research areas, which included material behavior and fracture evaluation and design of welded aluminum structures subjected to dynamic loading. In order to meet the Navy’s needs for a lightweight, high speed aluminum vessels, a new, accurate and efficient analysis and limit state based design methodology for welded aluminum ship structures is proposed. The proposed methodology accounts for anisotropic, nonlinear and rate dependent behavior of aluminum sheets, subjected to dynamic loads causing fracture and failure of structural components. A comprehensive analysis and design toolkit will be developed, allowing for better estimates of the ultimate strength and design safety factors. Substantially more efficient, accurate and rational design of high speed aluminum ships will result, which could lead to great savings in military and commercial applications.