Finite element model updating of a concrete arch bridge through static and dynamic measurements

Finite element (FE) analyses are increasingly used to make decision whether strengthening, repair or replacement of bridges are needed. These decisions can only be as good as the results from the analyses, and therefore a reliable and accurate model is decisive for good assessment and management. This paper describes how field test and monitoring results were used in combination for manual model refinement and non-linear optimization to obtain a more realistic FE model of one of the world’s largest single arch bridges, the New Svinesund Bridge. Measured strains, forces and deflections from a load test and measured eigenfrequencies under ambient excitation were used to update the initial model of the bridge.It was shown that different types of measurements are needed for updating a FE model that should be generally improved for dynamic and static analysis. The combination of manual refinements and updating though non-linear optimization led to an FE model that reproduced all measured parameters with significantly improved accuracy