Underwater Blast Response of Weathered Carbon Composite Plates

An experimental study was conducted to evaluate the response of weathered unidirectional composite plates subjected to near-field blast loading. The composite materials in this study are carbon-epoxy composite plates with a [45, −45]s layup and was subjected to simulated marine aging through submersion in seawater baths for 70 days at 65 degrees Celsius in order to simulate approximately 20 years of real life operating conditions. Experiments were performed by fully clamping the specimen plates to an air-backed enclosure in a water tank. An RP-503 explosive was placed underwater behind the composite structure to be loaded. During the experiments, transducers measured the pressure emitted by the explosive, and three high-speed cameras captured the entire event. Two of the cameras were placed apart facing the specimen to measure full-field displacements through 3-D Digital Image Correlation analysis. Results show that the diffusion of water into the composite material leads to degradation of the blast response behavior as well as a loss of flexural strength and modulus.