LAUSR

ABSTRACT The uncertainties widely exist in the engineering structures. Though great progress has been made in the study of the finite element (FE) modelling and updating with uncertainty, most model updating methods with uncertainty still suffer from the complexity of implementation. A novel FE model updating method in the structural dynamics with uncertainty is proposed in the paper. The model updating with interval uncertainty consists of two steps. In step one, the response surface model (RSM) between the natural frequency and the updating parameters is constructed according to the quadratic polynomial, and the interval average value of uncertain parameters is identified based on an optimal algorithm and the adaptive response surface model. Then, The half width of interval parameter is identified by combining the RSM and the sensitivity analysis in step two. A significant advantage of the proposed method is that it makes the interval model updating to be understood and implemented in the engineering application more easily. Finally, the proposed method is validated in a two degree-of-freedom mass-spring system and a transport mirror system. The updating results evidently demonstrate the feasibility and reliability of this method.