On dynamic finite element analysis of viscoplastic thin-walled structures with non-local damage: A phase-field approach

[EN] In this work, a nonlocal damage model is proposed for dynamic analysis of viscoplastic shell structures using the phase-field approach. A phase-field variable on the mid surface is introduced to characterize the nonlocal damage as well as the transition between undamaged and damaged phase. The total free energy in [1] is modified as a sum of Helmholtz free-energy and Ginzburg-Landau one. The latter is defined as a function of the phase-field variable and its corresponding gradient. This enhancement gives rise to an introduction of gradient parameters in terms of a substructure-related intrinsic length-scale. The evolution of the phase-field based damage variable can be found from the minimum principle of the dissipation potential [3]. The performance of the proposed model is demonstrated through numerical results of a plate with a circular hole. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)