MODAL PARAMETER IDENTIFICATION RESEARCH FOR THE EXTENDED EIGENSYSTEM REALIZATION ALGORITHM

The dynamic responses, as the input data of modal parameters identification, would affect the identification results whichever the identification method could be used. As one of the modal parameters identification with multi-input and multi-output in a time domain, the extended eigensystem realization algorithm (EERA) could be directly applied for an arbitrary random forced vibration system with the advantage of high accuracy, stable and so on. The paper identifies the modal parameters of two kinds of models, 2-NDof spring-damping-mass system for numerical model and 6-story frame structure for experimental model, via EERA with the 3 different sets of input responses of acceleration, velocity and displacement. The conclusions show that EERA could apply to any dynamic response without any code change, and acceleration response should be used when higher modes need to be identified.