Gradient-Enhanced Modelling of Damage for Rate-Dependent Material Behaviour-A Parameter Identification Framework

Materials (Basel). 2020 Jul 15;13(14):3156. doi: 10.3390/ma13143156.

Abstract

The simulation of complex engineering components and structures under loads requires the formulation and adequate calibration of appropriate material models. This work introduces an optimisation-based scheme for the calibration of viscoelastic material models that are coupled to gradient-enhanced damage in a finite strain setting. The parameter identification scheme is applied to a self-diagnostic poly(dimethylsiloxane) (PDMS) elastomer, where so-called mechanophore units are incorporated within the polymeric microstructure. The present contribution, however, focuses on the purely mechanical response of the material, combining experiments with homogeneous and inhomogeneous states of deformation. In effect, the results provided lay the groundwork for a future extension of the proposed parameter identification framework, where additional field-data provided by the self-diagnostic capabilities can be incorporated into the optimisation scheme.

Keywords: finite elements; gradient-enhanced damage at large strains; parameter identification; rate-dependent material behaviour.