Finite element model updating of canonica bridge using experimental modal data and genetic algorithm

This paper calibrates the finite element model (FEM) of a tied-arch bridge using an automatic model updating procedure developed within two softwares. The former is used for sensitivity analysis and optimization analysis while the latter is responsible for structural modeling and eigenvalue analysis. An interface connecting two softwares is first developed, as well as the procedure to calibrate the FEM. Based on the original drawing and topographic survey, the FEM of the investigated bridge is created. To obtain the experimental modal parameters, eight global modes of the studied bridge are identified by ambient vibration tests and the frequency domain decomposition technique. Then, the sensitivity analysis and FEM updating procedure is conducted and the optimal structural parameters are identified. Finally, the updated FEM is verified by a series of static tests. Results show that the updated model could better represent the actual bridge. Therefore, the numerical model updated by the proposed procedure could be further used for damage identification of the bridge under service loads.