Finite Element Model Updating

Abstract

This thesis focuses on engineering, specifically structural, systems that are approximated by finite element models (FEMs). Initial FEMs are found to have poor accuracies and improved or updated models are sort. From the literature we note that a common set of challenges still persists in all FEM work. These are; which aspects of the model are most uncertain, how can we efficiently update the model and finally how do we know that our chosen model is the best for the system at hand. This is the finite element model updating problem.These challenges are reinforced by the number of different FEMs that can be proposed for any one system and the difficulty of determining the best model from these. Moreover all the said challenges are applicable to all possible FEMs.To address these challenges we propose that the FEM updating problem be analyzed in a multi-model context. What is implicit in this proposal is that updating one model in isolation will not be very informative. This proposed I would like to thank my parents; Lindiwe and Shole Mthembu for their unwavering support, guidance and giving me a better background than they had. I would also like to thank my sister, Sindi and brother Menzi for their support and companionship. I would like to thank Namwawa Siwale for the encouragement, patience and support throughout this thesis. I would also like to thank Professor Tshilidzi Marwala for his encouragement and supervision during this work. In addition I thank Professors Michael Friswell and Sondipon Adhikari for their insights and recommendations during this thesis.