Finite-Element Analysis of Rate-Dependent Buckling and Postbuckling of Viscoelastic-Layered Composites

Abstract

The buckling and postbuckling responses of viscoelastic-layered composites are investigated using finite-element simulations. These composites consist of alternating layers of a stiff elastic constituent and of a soft viscoelastic constituent. In response to compressive loads in the layer direction, elastic instabilities significantly affect the finite deformation mechanics of these composites. The dependence of the critical strain and critical wavenumber on strain rate is analyzed. In the postbuckling regime, the wavenumber of the mode of deformation is found to be highly dependent on strain rate and time and can be used to identify three different regimes that depend on the volume fraction of the stiff constituent. Interestingly, a transition from a wrinkling mode to a longwave mode can be observed when the strain rate is varied for moderate volume fractions of the stiff material. Analytical formulae for the buckling and postbuckling of the elastic-layered composites are used to interpret numerical results obtained for viscoelastic-layered composites. Viscoelastic-layered composites exhibit a wide range of rate-dependent mechanical behavior and could have applications in vibration damping and acoustic metamaterials.

Towards mechanical characterization of soft digital materials for multimaterial 3D-printing

“…Ratedependent behavior of the DMs drastically increases the complexity of the constitutive models, but however, it is of importance for accurate modeling of the materials and predictions of their behavior. For example, the studies by [24,26] showed that viscoelasticity leads to an increased tunability of wrinkling patterns, occurring in the soft laminates. Rate dependency and non-linearities due to large deformations are the essential aspects of rich mechanical behavior of the soft DMs used in multimaterial 3D-printing.…”

“…The modeled stress-strain curves under the assumption of (25) and(26) for different values of contrast in long-term shear modules and relaxation times between volumetric and deviatoric parts of the strain tensor.…”

Nonlinear post‐buckling analysis of viscoelastic nano‐scaled beams by nonlocal integral finite element method

“…They also showed that because the loading rate was low, the inertia and damping effects did not have a pronounced effect on the postbuckling response. Alur et al [40] have studied the buckling and postbuckling responses of viscoelastic-layered composites using finite-element simulations. They discussed the dependence of the critical strain and critical wave number on strain rate.…”

“…Alur et al. [40] have studied the buckling and postbuckling responses of viscoelastic‐layered composites using finite‐element simulations. They discussed the dependence of the critical strain and critical wave number on strain rate.…”