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This paper reports the step-by-step procedures of a full-scale ambient vibration test and the corresponding modal identification and Bayesian structural model updating of a coupled building. The building is characterized as a combination of a main part and a complementary part connected together by corridors in between. Compared with the main part, the volume of the complementary part is much smaller. Therefore, the influence on the dynamic properties of the complementary part from its counterpart is expected. To capture the dynamic properties of the coupled building, a 21-setup ambient vibration test was designed to cover all the degrees of freedom (DOFs) of interest. The modal parameters of each setup were identified following the frequency domain decomposition (FDD) method and the partial mode shapes from different setups were assembled following a least-squares method. To determine the stiffness of the linkage between the two parts, the coupled building was simulated with two linked shear buildings and updated utilizing the Markov chain Monte Carlo (MCMC)-based Bayesian model updating method. The identified modal parameters revealed interesting features about the coupled effects between the main part and complementary part and were discussed in detail. The good match between the model-predicted and identified modal parameters verified the validity of proposed shear building model. This study provides valuable experience in the area of structural model updating and structural health monitoring. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a comprehensive study of the full‐scale ambient vibration test, modal analysis, finite element (FE) modeling, and model updating of a coupled building in Hong Kong. The coupled building comprised a main part and a complementary part. To capture the dynamic properties of the building, a 21‐setup ambient vibration test was designed and conducted. The modal parameters of each setup were identified following a fast Bayesian fast Fourier transform approach, and the partial mode shapes from the different setups were assembled following the least squares method. The identified modal parameters were analyzed and discussed in detail, revealing certain features of the coupling effects between the main and complementary parts. To determine the equivalent Young's moduli of various structural components, an FE model of the coupled building was developed and updated with the identified modal parameters. The Bayesian approach was followed to explicitly handle the uncertainties induced by modeling error and measurement noise. To ensure the model updating method is applicable even in unidentifiable cases, a Markov chain Monte Carlo simulation was employed in the proposed method to generate samples for approximating the posterior probability density functions of uncertain model parameters. The close match between the modal parameters calculated from the updated FE model and those identified from the measured time‐domain data verified the validity of the proposed FE model. This study provides valuable experience and information for the development of structural model updating and structural health monitoring of building systems. [ABSTRACT FROM AUTHOR]