Identification of modal parameters from ambient vibration data by modified eigensystem realization algorithm

In the present paper, we propose a modification to the Eigen system Realization Algorithm with Data Correlation (ERA/DC) for modal-parameter identification of structural systems subjected to stationary white-noise ambient vibration. By setting up a correlation-function matrix of stationary responses and introducing an appropriate factorization of the matrix, modal parameters of a system could then be effectively identified through the singular-value decomposition and eigenvalue analysis. Through numerical simulations, effectiveness and robustness of the proposed identification method is demonstrated.