In this contribution, the authors analyse the evolution of the internal damage by using X-ray computed tomography on a 3mm-diametre specimen. The specimen is tested in consecutive loading steps, after each of which it is unloaded and analysed with a X-ray tomograph. This procedure helps to identify the evolution of damage developed inside the specimen at predefined strain levels. Finally, these results are compared with the numerical results provided by the GTN model.
Suárez-Guerra et al. (2015) studied this question.