Title: Experimental Verification of Modal Identification of a High‑rise Building Using Independent Component Analysis

Author(s): Jae‑Seung Hwang, Jung‑Tae Noh, Sang‑Hyun Lee and Ahsan Kareem

Publication: IJCSM

Volume: 13

Issue:

Appears on pages(s):

Keywords: independent component analysis, mode decomposition, Hilbert transform, instantaneous natural frequency, derivative of covariance, output-only modal analysis

DOI: 10.1186/s40069-018-0319-7

Date: 2/28/2019

Abstract:
Independent component analysis is one of the linear transformation methods based the techniques for separating blind sources from the output signals of the system. Recently, the method has been analytically applied to the identification of mode shapes and modal responses from the output signal of structures. This study aims to experimentally validate the blind source separation using ICA method and propose a novel method for identification of the modal parameters from the decomposed modal responses. The result of the experimental testing on the three-story steel scale model shows that the mode shapes obtained by ICA method are in good agreement with those by the analytical and peak-picking method in the frequency domain. Based on the robust mathematical model, ICA can calculate the natural frequency and damping ratio effectively using the probability distribution function of the instantaneous natural frequency determined by Hilbert transform of the decomposed modal responses and the change in the output covariance. Finally, the validity of the proposed method paves the way for more effective output-only modal identification for assessment of existing steel-concrete buildings.