Evaluating Initial Model for Dynamic Model Updating: Criteria and Application

Finite element model updating is an important research field in structural dynamics. Though varieties of updating methods have been proposed in the past decades, all the methods could be effective only on the assumption that the initial finite element model is updatable. The assumption has led to the fact that all researchers study on how to update the model while seldom of them study on whether the model is updatable. This has become inevitable obstacle between research and engineering application because the assumption is not a tenable hypothesis in practice. Two criteria of evaluating initial models are given in this paper. A beam is employed in the numerical simulations. Two different initial models for the beam are constructed with correct and erroneous modeling of boundary condition respectively. The models are first evaluated using the proposed criteria and then updated using sensitivity based model updating method. The results indicate that the criteria are able to distinguish the model updatability.