Comparative finite element model updating of CBAR-based joint structure using iterative least square method and response surface methodology

Finite element model updating is an important method that often used to improve the accuracy of finite element analysis (FEA) especially for complex structure that consists of joint such as welded and bolted connections. Due to problem of uncertainties particularly for model with joining, traditional FE model usually exhibit discrepancies when compared to experimental data. This study aims to compare the approach of model updating by the iterative least square method by using SOL200 in MSC. Nastran/Patran software with response surface methodology (RSM) for a FE model with joining elements. The results show significant initial discrepancies on the model. Both approach of model updating successfully reduce the average percentage of error for the constructed FE models. However, the results indicate that iterative method that employ SOL200 able to provide slightly better accuracy. This study has contributed a comparative understanding on approaches of model updating which show both iterative and statistical method are able to improve accuracy in natural frequency predictions for welded and bolted models.