A Bayesian estimation method for variational phase-field fracture problems

Comput Mech. 2020;66(4):827-849. doi: 10.1007/s00466-020-01876-4. Epub 2020 Jul 14.

Abstract

In this work, we propose a parameter estimation framework for fracture propagation problems. The fracture problem is described by a phase-field method. Parameter estimation is realized with a Bayesian approach. Here, the focus is on uncertainties arising in the solid material parameters and the critical energy release rate. A reference value (obtained on a sufficiently refined mesh) as the replacement of measurement data will be chosen, and their posterior distribution is obtained. Due to time- and mesh dependencies of the problem, the computational costs can be high. Using Bayesian inversion, we solve the problem on a relatively coarse mesh and fit the parameters. In several numerical examples our proposed framework is substantiated and the obtained load-displacement curves, that are usually the target functions, are matched with the reference values.

Keywords: Bayesian estimation; Brittle fracture; Inverse problem; Multi-field problem; Phase-field propagation.