An Improved SSI Approach for Structural Modal Identification

Abstract

This paper proposes an improved Stochastic Subspace Identification (SSI) approach for structural modal identification. The automated interpretation of the SSI output, namely the stabilization diagram, is conducted based on the defined hard criteria and the used clustering techniques. To validate the performance of the proposed approach, numerical studies on a steel frame model are conducted and the ambient vibration measurements contaminated with a significant noise effect are used for identification. Experimental testing data are also used for the structural modal identification with the proposed approach. The accuracy and robustness of the proposed approach are demonstrated by the successful identification of modal parameters.