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The dispersion curves for harmonic waves in composite cylindrical elastic solids with a coating, made of non traditional soft material (nematic elastomer) are investigated. The obtained earlier low frequency effective model of nematics is used with taking into account the anisotropy, viscosity and internal rotation of long molecules of material. The impedance matrices, dispersion equations and asymptotics of speeds and wavenumbers in the long-wave approximation are derived for the further numerical analysis. The obtained quasi resonance effects of the first and of the second kinds are discussed for waves of different polarization. [ABSTRACT FROM AUTHOR]

Phase speeds and attenuations of symmetrical and antisymmetrical waves with PSV polarization in a heterogeneous composite plate with an elastic core and nematic elastomer coating are studied. The nematics are characterized not only by strong anisotropy of the viscoelastic properties, but also by an additional degree of freedom that allows rotation of long molecules and chains with respect to the main orientation direction. The analysis is based on an effective model of such a medium developed previously for description of isothermal low-frequency processes. This model made it possible to find specific effects of polarization of acoustic waves in infinite media. These extraordinary polarization effects lead to the quasi-resonance phenomena in an elastonematic composite as considered. [ABSTRACT FROM AUTHOR]

A problem of the dynamic behavior of an elastic layer coupled to one or two thick elastic solids is considered. All the materials may possess a general anisotropy and the layer is assumed to be thin enough with respect to the characteristic wavelength. Introducing the asymptotic power series with respect to the thickness-over-wavelength ratio for the main quantities and using the asymptotic integration method the displacements and stresses on the layer surfaces are related. Thus, the so-called impedance boundary conditions (IBC) are deduced for three cases—for a coated substrate with given displacements or with given stresses on the surface and for two substrates with a layer in between. In contrast to previous papers these IBC are obtained for the most general situation with the asymptotic accuracy up to the sixth order, uniform with respect to the representation of the displacements and stresses. Presented theory can be used for studying the surface and interface phenomena as well as for calculating fields and spectra of layered solids. The results are validated numerically and compared with those of other authors. [ABSTRACT FROM AUTHOR]

Rayleigh-type flexural waves localized near the edge of a thin anisotropic layered plate are investigated. The following effects are revealed: a wave attenuation with oscillations, a change of sign of the energy flux for certain types of anisotropy, and the appearance of stationary waves. [ABSTRACT FROM AUTHOR]

Within the scope of linear elasticity, the in-plane problem of an anisotropic plate or laminate with a circular hole and an elliptical hole reinforcement is considered. Arbitrary anisotropic elastic stiffnesses are allowed for the base plate and the reinforcement material, and for the reinforcement there is no restriction for its elliptical shape and size. The analysis of the problem is performed by the complex potential method with appropriately chosen series representations inside and outside the reinforcement region. The derived closed-form solution provides all resultant in-plane stresses and deformations within and around the hole reinforcement with little computational effort and at high accuracy. The determined solution allows a proper and effective assessment of hole reinforcements for many technical applications. [ABSTRACT FROM AUTHOR]

Exact solutions are obtained in the framework of the classical theory of laminates subjected to the action of normal moments, double forces, double moments or momentless double dipoles. Seven cases of such loads are considered and completed by considering the case of given transversal discontinuity of normal deflection. It is shown that, in contrast to the case of infinite straight dislocations in a pure in-plane problem, the energy of this eighth solution depends on the discontinuity orientation. Some numerical examples are presented. Besides the formal value, the obtained double-force and double-moment solutions, as well as dimensionless double dipoles, can be used to construct kernels of additional boundary integral equations (BIE). Due to the coupling phenomena in the BIE system for the region with a corner point, additional variable such as corner forces appear and require the mentioned equation. [ABSTRACT FROM AUTHOR]