Modelling and updating of large surface-to-surface joints in the AWE-MACE structure

Model updating of joints in the AWE-MACE system is carried out using a sensitivity method. The joints are characterised by large surface-to-surface contact regions and are excited in vibration tests within the linear range. The joints are modelled using a layer of special interface elements having material properties that may be adjusted to improve the prediction of the complete model. A series of three updating exercises are described and it is shown that by using only six parameters based upon the circumferential-wave and bending modes that the prediction of the axial and torsional modes is improved sufficiently to be of practical usefulness for many applications. Fewer numbers of updating parameters are found to be sufficient to correct different subsets of vibration modes. Linear equivalent models identified by this approach are found to be valid within the usual range of vibration tests.