Structural finite element model updating by using response surfaces and radial basis functions

Abstract

Updating a finite element model of a large and complex structure involves a large number of updating parameters, some of which may be insensitive to structural measurements. Updating them wastes computing time and easily yields false-positive results. Model updating of response surfaces based on radial basis functions has previously been demonstrated to alleviate these problems. This study was designed to further validate the effectiveness and feasibility of the method for real-world civil engineering structures. The model updating procedure is illustrated in detail using a theoretical structure, a laboratory-scale bridge model, and an actual bridge. The key issues in selecting parameters and responses for updating are discussed. An objective function is proposed based on the differences between model predictions and measured responses. The alternatives of model updating solutions are discussed to obtain an optimal result. On the basis of the numerical simulation, experimental study, and real bridge application, the results indicate that this method works well and can easily be implemented in practice for updating models of complex bridges such as long-span, cable-stayed bridges.