Experimental and Numerical Analyses of Dynamic Deformation and Failure in Marine Structures Subjected to Underwater Impulsive Loads.

摘要

Marine structures are designed to operate in hostile environments consisting of corrosive sea-water, hot and cold temperature extremes, transient dynamic loads like hull-slamming and complex three-dimensional hydrostatic loads. Additionally, naval structures are required to withstand weapons impacts and blast loads resulting from surface and underwater explosions. Recent assessments of marine structures have demonstrated that sandwich structures and composite materials can provide high strength-to-weight ratios and good blast mitigation. This thesis is focused on the dynamic response of composite materials and structures to underwater impulsive loading. This research work seeks to establish structure-material-property relationships for marine structures based on different materials, loading intensities and novel structural design concepts to enhance the blastresistance of naval structures. Of particular interest are experimental and computational evaluations of the physical processes involved in the dynamic response of fiberreinforced composite materials and composite sandwich. This research work encompasses blast/shock loading; rupture and penetration; Fluid Structure Interaction (FSI) effects; dynamic constitutive relations and strain-rate effects; damage- modeling; and concepts for damage mitigation.