Vibration-based Bayesian model updating of civil engineering structures applying Gaussian process metamodel

Abstract

Structural health monitoring plays a significant role in providing information regarding the performance of structures throughout their life spans. However, information that is directly extracted from monitored data is usually susceptible to uncertainties and not reliable enough to be used for structural investigations. Finite element model updating is an accredited framework that reliably identifies structural behavior. Recently, the modular Bayesian approach has emerged as a probabilistic technique in calibrating the finite element model of structures and comprehensively addressing uncertainties. However, few studies have investigated its performance on real structures. In this article, modular Bayesian approach is applied to calibrate the finite element model of a lab-scaled concrete box girder bridge. This study is the first to use the modular Bayesian approach to update the initial finite element model of a real structure for two states—undamaged and damaged conditions—in which the damaged state represents changes in structural parameters as a result of aging or overloading. The application of the modular Bayesian approach in the two states provides an opportunity to examine the performance of the approach with observed evidence. A discrepancy function is used to identify the deviation between the outputs of the experimental and numerical models. To alleviate computational burden, the numerical model and the model discrepancy function are replaced by Gaussian processes. Results indicate a significant reduction in the stiffness of concrete in the damaged state, which is identical to cracks observed on the body of the structure. The discrepancy function reaches satisfying ranges in both states, which implies that the properties of the structure are predicted accurately. Consequently, the proposed methodology contributes to a more reliable judgment about structural safety.

Computation-Effective Structural Performance Assessment Using Gaussian Process-Based Finite Element Model Updating and Reliability Analysis

“…This section refers to the model updating technique applied in this work.An approach to incorporate uncertainty in different stages of a FEMU process will be briefly described. For more details of the approach, refer to Moravej et al (2019a.The comprehensive relationbetweenobservations (i.e., measured structural response) and a numerical modelcan be statedin Eq. 1…”

“…This method substitutesa Gaussian process (GP) model with FE model, which is a surrogate model. It has been observed that the method considerablydecreases computational effort,and it is believed to be the most appropriate approach to update a FE model under uncertainty (Conde et al 2018;Jesus et al 2014;Jesus et al 2017;Jesus et al 2019a;Jesus et al 2019b;Lophaven et al 2002). The GP model for interpolation/extrapolationwith the capability for addressing uncertainties is found to be effective, even with limited data.…”

“…The acceleration responses of the structure in thetwo states were recorded and applied in the FEMU process. The applied sensory system for this workcan be found in Moravej et al (2019a) and Nguyen et al (2017). Priorto select anaccurate sensor arrangement, different featureshave beennoted,such as the type and number of existing sensors, the requiredquantity of channels in the data acquisition set, and the excitation resource.…”

Progressive numerical model validation of a bowstring-arch railway bridge based on a structural health monitoring system

“…An accurate and reliable assessment of the structural safety of railway bridges based on numerical models depends, however, on their experimental validation under environmental and traffic actions, and, in some situations, it may be necessary to update the model, which typically involves adjustments to specific parameters of the model to increase the correlation between numerical and experimental data [9][10][11]. Numerous works that address model validation can be found in the literature, using not only direct measurements under static and dynamic loads, such as strains, displacements and accelerations [12,13], but also, and more commonly, modal information, such as natural frequencies, damping and mode shapes based on acceleration measurements [10,[14][15][16]. Tomé et al [17] showed the need to develop a complex 3D beam FE model to successfully analyse the static structural response of a concrete cable-stayed bridge equipped with a permanent monitoring system, under the effects of temperature variations.…”

Analysis of Seismic Action on the Tie Rod System in Historic Buildings Using Finite Element Model Updating

“…It refers to updating the finite element (FE) numerical model to adopt more precise and accurate structural dynamics parameters based on the known dynamics or statical parameters obtained through experimental investigations of a structure [12][13][14][15][16] (Figure 2). During the model updating procedure, the most commonly used model updating parameters are the material [16][17][18][19][20][21][22][23] and geometrical characteristics [23][24][25][26] and boundary conditions [27][28][29], but their selection is generally based on performing the sensitivity analysis [30]. The selection of materials and the definition of their properties cause great difficulties in the development of a numerical model due to their specific mechanical properties.…”