Finite-element model updating using experimental test data: parametrization and regularization

Two critical issues in model updating are deciding how a finite-element mod el should be parametrized and estimating the unknown parameters from the re sulting ill-conditioned equations. A lack of understanding of these issues will lead to updated models without physical meaning. This paper outlines t he authors' approach to parametrization, using physical, geometric and gene ric element parameters. It also applies useful methods of regularization, n amely parameter constraints, the singular-value decomposition, L-curves and cross-validation to model updating.