Reliability Analysis of Gravity-based Offshore Wind Turbine Foundation Considering Ocean Environmental Loads and Soil Uncertainty

해양환경하중 및 지반의 불확실성을 고려한 중력식 해상풍력 기초의 신뢰성 해석

Lee, Sang Geun;Kim, Dong Hyawn

  • Received : 2014.11.21
  • Accepted : 2015.10.22
  • Published : 2015.10.31


A reliability analysis of the gravity-based foundation of anoffshore wind turbine was performed by considering the uncertainties of the design variables, including environmental loads. The limit state functions of the gravity-based foundation were defined using the response limits of the support structures suggested in the DNV standard. The wind load couldbe obtained using the GH_bladed software, and the wave load was calculated using the Morison equation. Then, the extreme distributions of the wind and wave loads were estimated by applying the peak over threshold (POT) method to the wind and wave load data. The probability distribution characteristics of the soil properties were defined with reference to a southwest coast geotechnical survey report. The reliability index was evaluated for each failure mode using a first-order reliability method.


Offshore wind turbine;Gravity-based foundation;Reliability analysis;First-order reliability method(FORM)


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