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http://dx.doi.org/10.5762/KAIS.2017.18.8.64

Damage Estimation Method for Jacket-type Support Structure of Offshore Wind Turbine  

Lee, Jong-Won (Department of Architectural Engineering, Namseoul University)
Publication Information
Journal of the Korea Academia-Industrial cooperation Society / v.18, no.8, 2017 , pp. 64-71 More about this Journal
Abstract
A damage estimation method is presented for jacket-type support structure of offshore wind turbine using a change of modal properties due to damage and committee of neural networks for effective structural health monitoring. For more practical monitoring, it is necessary to monitor the critical and prospective damaged members with a limited number of measurement locations. That is, many data channels and sensors are needed to identify all the members appropriately because the jacket-type support structure has many members. This is inappropriate considering economical and practical health monitoring. Therefore, intensive damage estimation for the critical members using a limited number of the measurement locations is carried out in this study. An analytical model for a jacket-type support structure which can be applied for a 5 MW offshore wind turbine is established, and a training pattern is generated using the numerical simulations. Twenty damage cases are estimated using the proposed method. The identified damage locations and severities agree reasonably well with the exact values and the accuracy of the estimation can be improved by applying the committee of neural networks. A verification experiment is carried out, and the damage arising in 3 damage cases is reasonably identified.
Keywords
Committee of neural networks; Critical members; Damage estimation; Jacket-type support structure; Modal property;
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