Characterization of Hydrodynamic Properties from Free Vibration Tests of a Large-Scale Bridge Model
Sponsor
A financial support was provided by The Higher Committee of Education Development (HCED) of Iraq for Alaa W. Hameed’s to study at Portland State University.
Published In
Journal of Fluids and Structures
Document Type
Citation
Publication Date
10-1-2021
Abstract
To accurately predict the dynamic response of a structure subjected to fluid induced loading, a thorough understanding of the dynamic properties (mass, stiffness, and damping) and associated interactions is required. Limited data are available to characterize dynamic fluid–structure interactions. Data are particularly limited for large-scale and flexible structural models. This article reports the results of the first free vibration tests of a dynamic large-scale laboratory highway bridge superstructure model. The dynamic response characteristics of the model were extracted and analyzed from free vibration tests under varying levels of water submersion and for different horizontal substructure flexibilities. The nature of the damping response was identified based on the empirically measured logarithmic decrements of the model’s free vibration displacement amplitudes, and a suitable equation of motion (EOM) was subsequently developed. Using the classical fourth-order Runge–Kutta method, the EOM was solved for the different test trials and the dynamic properties of the model were obtained through an optimization approach. The concept of added mass was introduced to explain the observed decrease in natural frequency with increasing levels of water submersion. Finally, added mass factor was computed for the case where the water level was even with the top of the bridge superstructure model. This study provides a suitable EOM needed for numerical simulations of this and similar models that study fluid–structure interaction and also provides a methodology for establishing the structural dynamic properties of generalized hydrodynamic analytical models.
Rights
© 2021 Elsevier Ltd. All rights reserved.
Locate the Document
DOI
10.1016/j.jfluidstructs.2021.103368
Persistent Identifier
https://archives.pdx.edu/ds/psu/39017
Citation Details
Schumacher, T., Hameed, A. W., Higgins, C., & Erickson, B. (2021). Characterization of hydrodynamic properties from free vibration tests of a large-scale bridge model. Journal of Fluids and Structures, 106, 103368. https://doi.org/10.1016/j.jfluidstructs.2021.103368