An output-only stochastic parametric approach for the identification of linear and nonlinear structures under random base excitations: Advances and comparisons

In this paper a time domain output-only Dynamic Identification approach for Civil Structures (DICS) first formulated some years ago is reviewed and presented in a more generalized form. The approach in question, suitable for multi- and single-degrees-of-freedom systems, is based on the statistical moments and on the correlation functions of the response to base random excitations. The solving equations are obtained by applying the Itô differential stochastic calculus to some functions of the response. In the previous version ([21] and [22]), the DICS method was based on the use of two classes of models (Restricted Potential Models and Linear Mass Proportional Damping Models) while its generalization for use with different models from the ones mentioned above is discussed. In the paper the new class of models to which the DICS method is applicable are described. Further, the advantages and disadvantages of the approach in question are examined, also by a comparison with some techniques available in the literature.