DAMAGE identification with fusion of estimates from covariance of IRF in different frequency bands. (1st December 2019)

• Record Type: Journal Article
• Authors: Li, X.Y.; Ye, X.Q.; Law, S.S.
• Is Part Of: Mechanical systems and signal processing. Volume 134(2019)
• Publication Date: 2019-12-01
• Subjects: Damage identification -- Wavelet packet energy -- Covariance -- Bayesian fusion -- Acceleration; Structural dynamics -- Periodicals; Vibration -- Periodicals; Constructions -- Dynamique -- Périodiques; Vibration -- Périodiques; Structural dynamics; Vibration; Periodicals; 621
• DOI: 10.1016/j.ymssp.2019.106327
• Languages: English
• ISSNs: 0888-3270

Abstract

Highlights: The analytical formula of CoI of every mode is derived. CoI sensitivity is obtained analytically. CoI and WPE changes and Bayesian fusion are used without need of analytical model. Numerical study and Experimental verification are performed. Abstract: Structural health monitoring is becoming more important for infrastructure worldwide in the past few decades. An accurate analytical model of the monitored engineering structure is, however, usually not available. This report presents a new non-model based damage detection method from variation of the auto (cross)-covariance of impulse response function within selected frequency bandwidths of responses obtained from the intact and damaged structural states. The covariance is computed via the wavelet packet of the responses. Bayesian fusion is applied to all the damage probability vectors obtained from the covariance under different excitations and different measurement noise. A seven-storey steel frame structure with scenarios of both single and multiple damages and complete or incomplete measurements is numerically analyzed. A similar frame was later test in the laboratory with hammer excitation. The sensors nearest to the local damages exhibit the biggest damage probability. Both numerical and experimental results show that the proposed method is effective and promising for damage detection of practical engineering structures.