Wave slamming was simulated by repeatedly slamming rectangular sandwich composite specimens mounted on a rigid wedge with constant deadrise angle onto the body of calm water at various energy levels. Under single slamming, peak pressures and strains on the specimens were consistently found near the keel, whereas the maximum damage was localized near the chine. Significant reduction in strength was observed resulting from a single slam even at a moderate slamming energy level that left no apparent/visible damage to the test panel. Similarly, a substantial reduction in strength was observed under repeated slamming at various energy levels. The results were corroborated with acoustic emission observations that indicated a substantial reduction in AE activity in slammed specimens. A methodology was developed for the quantitative assessment of remaining strength and damage accumulation in slammed specimens using AE technique. Face yielding and core crushing were found to be the dominant modes of failure.

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This research work focuses on the viability of applying a thermal method for detecting damage in carbon fiber and sandwich composites. The fundamental of the technique analyzed herein is based on changes in the temperature profiles as a heat flux travels through the material. A 3-D finite element simulation provides good qualitative results and an inexpensive tool for detecting the presence of damage and its exact location. The influence of parameters, such as damage depth, diameter, and limiting detection time is also studied. This thermal technique is also implemented experimentally in an attempt to detect damage. Experimental results are compared to the numerical simulations in terms of damage locations and temperature trends. Damage is detected experimentally for metal surfaces and carbon fiber composite materials with simple structural arrays. However, for honeycomb composite materials, the detection of damage from the thermal standpoint was somewhat difficult due to the complex temperature profile generated within the material, due to its complex array of materials.