SHOCK DAMAGE MECHANISM OF A SIMPLE STRUCTURE

Abstract : Two sets of four cantilever beams loaded with tip masses were mounted on a floating shock platform and shock tested by underwater explosions. These simple mechanical models were designed to undergo appreciable plastic deformations. Three analytical approaches to predict shock damage were applied to these beam - mass models: one considering elastic - perfectly plastic mode response; another considering an energy balance to predict displacement bounds; and the third considering an inelastic deformation mode approximation. The displacement bound and mode approximation methods were applied considering both elastic - perfectly plastic and rigid - perfectly plastic deformations. The analytical results were compared with experimental data. The elastic - perfectly plastic analysis shows good agreement with experiment up to the initial peak displacement. Computed elastic - plastic bounds and inelastic mode approximations also provide good estimations of the initial displacements. (Author)