Parameter identification of gradient enhanced damage models with the finite element method
نویسندگان
چکیده
In this contribution an algorithm for parameter identification of gradient enhanced damage models is proposed, in which non-uniform distributions of the state variables such as stresses, strains and damage variables are taken into account. To this end a least-squares functional consisting of experimental data and simulated data is minimized, whereby the latter are obtained with the Finite-Element-Method. In order to improve the efficiency of the minimization process, a gradient-based optimization algorithm is applied, and therefore the corresponding sensitivity analysis for the coupled variational problem is described in a systematic manner. For illustrative purpose, the performance of the algorithm is demonstrated for a square panel under tension, in which an isotropic gradient damage model is used. 1999 Èditions scientifiques et médicales Elsevier SAS gradient enhanced damage models / parameter identification / sensitivity analysis / optimization / finite element method
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