Advanced test simulator to reproduce experiments at small and large deformations

Abstract

Full field measurements and inverse methods can be conveniently used to identify the constitutive properties of materials. Several methods are available in the literature which can be applied to many different types of materials and constitutive models (linear elasticity, elasto-plasticity, hyper-elasticity, etc.). The effectiveness of the identification procedure is related to the specimen geometry and the quality of the optical measurement technique. A method to improve and optimize the identification procedure is to numerically simulate the whole process. In such a way it is possible to compare different configurations and chose the one that shows the lowest identification error. A test simulator was already developed by the authors and, in this paper, an improved version is presented. The simulator is now able to deal with small deformations thanks to a super-sampling algorithm which allows to reduce the numerical artefacts introduced during the image deformation. The simulated experiments are compared with actual ones. A series of experiments has been performed using aluminium specimens. The reliability of the simulated experiments is evaluated looking at the simulated and experimental displacement and strain maps and comparing the obtained identification errors. © The Society for Experimental Mechanics, Inc. 2014.