Concepedia

Abstract

Representation of frequency-dependent viscoelastic material properties has long been problematical in the frequency domain and especially in the time domain. The method of Golla, Hughes, and McTavish (GHM) addresses this problem with a Laplace-domain model of the complex material modulus, in which a number of parameters are determined by curve- fitting to experimental data. The result is well suited to finite element formulations because the equations of motion retain the familiar second-order, constant-coefficient form, at the expense of some extra scalar degrees of freedom. This paper reports on an implementation of GHM in MATLAB, using FEM data imported from NASTRAN. Sample problems demonstrate the efficacy and practicality of the method.