A updating method using strain frequency response function with emphasis on local structure

A dynamic finite element model updating method for the concerned local structure is presented using strain frequency response function test data. Firstly, a dynamic condensation technique is developed to establish the dynamic finite element model of the concerned local structure for improving the analytical efficiency of the dynamic strains and their transfer relations in model updating. Then, the sensitivity of strain frequency response function of the local structure is conducted to construct the canonical equation for model updating. Furthermore, a model updating strategy of ‘grouping-iteration’ is proposed to stabilize the ill-posed problem in the model updating process. Finally, numerical simulation and experimental investigation for updating the dynamic finite element model of the cantilever plate structure with elastic support are performed to validate the feasibility and efficiency of the present method. The obtained results show that the present method can be successfully used to update the dynamic finite element model of the local structure in terms of achieving a good agreement between the strain frequency response functions of the updated finite element model and the actual structure.