Structural Dynamics Model Updating Based On Feedback Control Techniques

Finite element model updating techniques is one of the most important directions in current structure dynamics research.Model updating has become increasingly active in the international study field these years which update the structural analysis model using test data to make good correlation of the modified data and test data and the exact description of the real structure.The content is as followed:In chapter 1,some required preparative knowledge including general symbols and basic lemmas are introduced.And,we simply introduce the work of the paper.In chapter 2,firstly,we discuss the problem of updating undamped dynamic systems based on feedback control techniques.By using the QR-decomposition and iterative method,the required control gain matrices of acceleration and displacement feedback are determined,and the optimal corrected mass and stiffness matrices are found under the Frobenius norm sense.This method can guarantee that updated matrices are symmetric and updated system is no spill-over.Second,we discuss the problem of updating undamped dynamic systems based on output feedback control techniques.By using the QR-decomposition and singular value decomposition and iterative method,the required control gain matrices of acceleration and displacement output feedback are determined,and the optimal corrected mass and stiffness matrices are found.This method can guarantee that updated matrices are symmetric and updated system is no spill-over.Finally,we discuss a class of special cases of the problem of updating undamped dynamic systems based on output feedback control techniques.At the end of each section,we give some numerical examples to show that the proposed method is reliable and attractive.In chapter 3,we discuss the problem of updating damped dynamic systems based on feedback control techniques.By using the QR-decomposition and iterative method,the required control gain matrices of velocity and displacement feedback are determined,and the optimal corrected damping and stiffness matrices are found under the Frobenius norm sense.The measured data are embedded in the new model and the symmetry of the original model are preserved.