Sandwich structures have shown improved structural efficiency as compared to monolithic structures. However, one area of concern in sandwich construction is the durability and damage tolerance of these structures. This concern is more severe in sandwich structures with composite face sheets as in-service foreign object impact can cause core damage and affect the load transfer between the face sheets. Damage due to sharp foreign objects such as engine blades, forklifts, etc. can penetrate through one or both the face sheets and result in the core damage. The proposed research program will develop and verify analytical tools for the optimum design of composite sandwich structures for damage containment. A mathematical method of analysis will be developed rather than a finite element technique. The analytical tool will evaluate if a damage arrestment mechanism is necessary in a sandwich structure. If arrestment mechanism is necessary, the analytical tools will suggest if it is needed in one or both the face sheets. In addition, the analytical tools will recommend the optimum size and spacing of the arrestment mechanism. The software program developed for mathematical analysis will be operational on a personal computer or a workstation.
Potential Commercial Applications:The proposed program will develop and demonstrate the design and analysis techniques that can be used for optimizing sandwich structures. The analytical techniques developed in the proposed program will provide efficient tools that can be used by the aerospace design personnel to design structurally efficient sandwich structures. This will significantly reduce the design time of aerospace structures. Sandwich structures technology has high potential applications to commercial aircraft. The software will assist in making decisions whether conventional skin/stinger type of construction or sandwich construction is more economical. R-Tec plans to market the software to commercial and military aircraft manufacturers. R-Tec plans to provide support services for the software to the users, maintain the software, and continuously add new capabilities.
