Damage detection in dolphin platform of a wharf by finite element model updating

Document Type : Research Article


1 Maritime Engineering, Amirkabir University of Technology

2 Faculty Member Amirkabir University of Technology

3 Department of maritime Engineering, Amirkabir University of Technology

4 National Iranian Oil engineering and construction Islamic Azad University-Tehran Jonoob branch


In this paper, the performance of a damage detection method based on power spectral density (PSD) is numerically investigated on the dolphin platform of a wharf used for the unloading of merchant ships. In this numerical investigation damage is modeled as a percent reduction in stiffness of the elements. For this purpose, the finite-element model of the dolphin is made in the MATLAB software and the effect of surrounding water is considered as the added mass on the elements. To realise the performance of the method on the dolphin model, several assumed damage scenarios with different levels of damage in the structure, are considered. Furthermore, an approach for calculation of the spectral density of excitation using an approximate FRF is introduced. Results prove the success of the method in the identification of the parameters of a stiff coastal structure like a dolphin. Besides, the results from these investigations prove that the added mass significantly affects the damage detection results. The quality and accuracy of the numerical results prove the merits of damage detection by finite-element model updating in the frequency domain. The results of the present study urge the practical assessment of the performance of the method in the future.


Main Subjects

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