Structural Health Monitoring of Submersible Navy Composites

The use of composite structural elements continues to expand across Naval Surface Ship and Submarine shipbuilding programs as advancements in design/analysis and research provide viable alternatives to current baseline material systems. To support life-cycle implications of using composites in a US Navy Submarine application, this proposal supports the initial Phase I development of a Structural Health Monitoring (SHM) system capable of detecting and characterizing damage in submersible composite non-pressure hull components. SHM is the scientific process of non-destructively identifying four characteristics related to the fitness of a structural system: (a) the operational and environmental loads that act on the structure; (b) the structural damage that is caused by that loading; (c) the growth of damage as the structure continues to be subjected to operational and environmental loads; and (d) the future performance of the structure as damage accumulates. This proposal assumes the SHM system should be compatible with VARTM and OVB fabrication processes, as well as compatible with carbon and glass systems with vinyl ester or epoxy resins. The intent of these initial efforts will be to first determine if the prescribed sensor system can be viably integrated into the composite structure, then to subject test specimens to representative wave slap, hydrostatic, impact and shock loading to determine if that system can not only survive these extreme loads, but continue to provide meaningful data throughout these events.