STRESS WAVE PROPAGATION IN ELASTIC-ELASTIC AND ELASTIC-VISCOELASTIC BILAMINATES

摘要

In the present study normal plate-impact experiments are conducted to investigate the propagation of acceleration waves inrn2-D layered material systems. The objective of these experiments is to understand the role of material architecture andrnmaterial inelasticity in controlling precursor decay and late-time dispersion of acceleration waves in elastic-elastic and elasticviscoelasticrnlaminates. The experiments are conducted using the 82.5 mm single-stage gas-gun facility at CWRU. The historyrnof the free-surface particle velocity at the rear surface of the target plate is measured by employing a VALYN VISAR. In orderrnto understand the effects of layer architecture, experiments are conducted on elastic-elastic bilaminates fabricated withrndifferent layer thicknesses and impedance mismatch. Moreover, in order to understand the effects of material inelasticity,rnexperiments on elastic-viscoelastic bilaminates are utilized. The results of the study indicate that the structure of accelerationrnwaves is strongly influenced by impedance mismatch of the layers constituting the bilaminates, density of interfaces, distancernof wave propagation, and the material inelasticity.