Vibration-Based Damage Detection Framework of Large-Scale Structural Systems

Abstract

The main objective of this work is to present a vibration-based damage estimation framework for structural systems by integrating vibration experimental measurements in a high-fidelity, large-scale, finite element (FE) model. Using the measured responses of a healthy structural system under operational vibrations, a parameterized FE model could be tuned using state-of-the-art FE model updating techniques in order to develop a high-fidelity model of the structural system, representing the healthy reference model. These methods provide much more comprehensive information about the condition of the monitored system than the analysis of raw data. The diagnosed degradation state, along with its identified uncertainties, can be incorporated into robust reliability tools for updating predictions on the residual useful lifetime of structural components and safety against various failure modes, taking into account stochastic models of future loading characteristics. A fault or damage would cause a sudden change in the operational responses of the structure. Incorporating the unhealthy response under measured operational excitations, a series of FE model updating runs of incrementally reparameterized FE models could be automated. The sensitivity of the unhealthy response to the parameter change pertains to the sensitive parts of the FE model, where damage or fault is located. A recursive reparameterization of those sensitive parts, followed by an FE model updating, leads toward both the detection localization and the type and magnitude of the fault or damage. The proposed framework is applied on a small-scale laboratory steel truss bridge. © 2022, The Society for Experimental Mechanics, Inc.