Summary: | Bolted joints in the assembled structure not only contribute to a change in dynamic behaviour but also increase the uncertainties in modelling and predicting dynamic behaviour. However, an accurate and efficient representation of bolted structures is often found to be difficult and has not been extensively presented in the literature, particularly with regard to the dynamic response of the bolted structure itself. This paper compares modelling methods capable of reducing uncertainties and increasing prediction accuracy. Two finite element (FE) models of bolted structures were developed using CBEAM, CELAS and either 3D or 2D elements representing the bolts, joint interfaces and structural components respectively. Normal modes analyses were performed for the FE models to predict the natural frequencies and mode shapes. Sensitivity analyses were formulated and used to identify the highly sensitive design parameters of both FE models. FE model updating was adopted to correlate the FE model with experimental modal analysis (EMA) to produce an updated FE model. It was found that the updated 2D FE model can predict the dynamic behaviour of the bolted joint better than the 3D model FE with an accuracy of 80.8 per cent. This proposed scheme showed the potential applicability for the subsequent analysis of the dynamic behaviour of complex bolted structures. © International Institute of Acoustics and Vibration (IIAV), 2022.
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