Harmonic Viscoelastic Waves Propagating Normal to the Layer of Laminated Media

抄録

The propagation of the harmonic viscoelastic waves in the laminated media in the direction normal to the layers is analyzed, and the frequency equations for the dilatational waves and the shear waves are formulated. The frequency-complex were number spectra are obtained for the laminated composites which consist of elastic reinforcing layers and viscoelastic matrix layers. And the phase velocity spectra and the attenuation spectra are investigated in the range of low frequencies. It is found that the phase velocity spectra for the viscoelastic dilatational waves show different features from those for the elastic waves. It is also found that even when the volume fraction of elastic layers is increased, the attenuation constant does not necessarily decrease, but that it has the largest value at a certain volume fraction.