A method of viscoelastic two-scale analyses for FRP

Abstract

The aim of this study is to propose a strategy for performing viscoelastic two-scale analyses for fiber-reinforced plastic (FRP) with periodic microstructures (unit cells), based on the assumption that the anisotropic generalized Maxwell model can be employed for the homogenized viscoelastic constitutive law. We first summarize a method of numerical material testing, for which the standard finite element method is applied to solve the extended system of micro-scale governing equations incorporated with external material points, or equivalently control nodes. Secondly, the anisotropic generalized Maxwell model is provided. Thirdly, we propose a method of parameter identification that uses the "measured data" by the numerical relaxation tests conducted with a relevant set of macroscopic strains. Finally, the trains of two-scale viscoelastic analyses is exemplified to demonstrate the validity of the proposed method.