This document deals with a method for eigenvalue extraction for the analysis of structures with viscoelastic materials. A generalized Maxwell model is used to model linear viscoelasticity. Such kind of model necessitates a state-space formulation to perform eigenvalue analysis with standard solvers. This formulation is very close to ADF formulation. The use of several materials on the same stru...

Viscoelastic materials have a relationship between stress and strain which depends on time or frequency. Anelastic solids represent a subset of viscoelastic materials: they have a unique equilibrium configuration and ultimately recover fully after removal of a transient load. Internal friction refers to the dissipative response of a material when subjected to a sinusoidal deformation. All mater...

The propagation of ultrasonic guided waves in viscoelastic isotropic material has been investigated. Based on the plane theory, a numerical model of the guided waves propagating is developed in the frequency domain by employing the SFEM (spectral finite element method). To verify the proposed method, thin bitumen on the steel substrate is examined and compared with the single plate in terms of ...

We establish the results on existence and exponent stability of solutions for a semilinear nonautonomous neutral stochastic evolution equation with finite delay; the linear part of this equation is dependent on time and generates a linear evolution system. The obtained results are applied to some neutral stochastic partial differential equations. These kinds of equations arise in systems relate...

Viscoelastic materials have non-negative relaxation spectra. This property implies that viscoelastic response functions satisfy certain necessary and sufficient conditions. It is shown that these conditions can be expressed in terms of each viscoelastic response function ranging over a cone. The elements of each cone are completely characterized by an integral representation. The 1:1 correspond...

We study mechanical behavior of soft rubber-like digital materials used in Polyjet multimaterial 3D-printing to create deformable composite materials and flexible structures. These soft digital materials are frequently treated as linear elastic materials in the literature. However, our experiments clearly show that these materials exhibit significant non-linearities under large strain regime. M...

We find some new results regarding the existence, uniqueness, boundedness, stability and attractivity of the solutions of a class of initialboundary-value problems characterized by a quasi-linear third order equation which may have non-autonomous forcing terms. The class includes equations arising in superconductor theory, quantum mechanics and in the theory of viscoelastic materials.

Wall displacements and ground pressure acting on the lining of a tunnel increase with time. These time-dependent deformations are both due to face advance effect and to the time-dependent behavior of the rock mass.  Viscoelastic materials exhibit both viscous and elastic behaviors. Thorough this study, the effect of different linear viscoelastic models including Maxwell, Kelvin and Kelvin-Voigt...

Batra [1] used a linear relationship between the second Piola-Kirchhoff stress tensor S and the Green-St. Venant strain tensor E to study finite simple shearing and finite simple extension deformations of an elastic body. In each case he found that the tangent modulus (i.e. the slope of the shear stress vs. the shear strain curve or the slope of the axial stress vs. the axial stretch curve) is ...

Rock-like materials are composites that can be regarded as a mixture composed of elastic, plastic, and viscous components. They exhibit viscoelastic-plastic behavior under a high-strain-rate loading according to element model theory. This paper presents an analytical solution for stress wave propagation in viscoelastic-plastic rock-like materials under a high-strain-rate loading and verifies th...