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A platform for research: civil engineering, architecture and urbanism
Stochastic dynamic stiffness of a surface footing for offshore wind turbines: Implementing a subset simulation method to estimate rare events
https://orcid.org/0000-0002-6414-5810
Abstract The purpose of this study, which concerns the stochastic dynamic stiffness of foundations for large offshore wind turbines, is to quantify uncertainties related to the first natural frequency of a turbine supported by a surface footing and to estimate the low event probabilities. Herein, a simple model of a wind turbine structure with equivalent coupled springs at the base is calibrated with the mean soil property values. A semianalytical solution, based on the Green׳s function for a layered half-space is utilized for estimation of foundation responses. Soil elastic modulus and layer depth are considered as random variables with lognormal distributions. The uncertainties are quantified, and the estimation of rare events of the first natural frequency is discussed through an advanced reliability approach based on subset simulation. This analysis represents a first step in the estimation of the safety with respect to the failure of a turbine in the fatigue limit state.
Highlights This study concerns the stochastic dynamic stiffness of foundations for large offshore wind turbines. A simple model of wind turbine structure with equivalent coupled springs at the base is utilized. The level of uncertainties is quantified through a sensitivity analysis. Estimation of rare events of first natural frequency applying subset simulation is discussed.
Stochastic dynamic stiffness of a surface footing for offshore wind turbines: Implementing a subset simulation method to estimate rare events
https://orcid.org/0000-0002-6414-5810
Abstract The purpose of this study, which concerns the stochastic dynamic stiffness of foundations for large offshore wind turbines, is to quantify uncertainties related to the first natural frequency of a turbine supported by a surface footing and to estimate the low event probabilities. Herein, a simple model of a wind turbine structure with equivalent coupled springs at the base is calibrated with the mean soil property values. A semianalytical solution, based on the Green׳s function for a layered half-space is utilized for estimation of foundation responses. Soil elastic modulus and layer depth are considered as random variables with lognormal distributions. The uncertainties are quantified, and the estimation of rare events of the first natural frequency is discussed through an advanced reliability approach based on subset simulation. This analysis represents a first step in the estimation of the safety with respect to the failure of a turbine in the fatigue limit state.
Highlights This study concerns the stochastic dynamic stiffness of foundations for large offshore wind turbines. A simple model of wind turbine structure with equivalent coupled springs at the base is utilized. The level of uncertainties is quantified through a sensitivity analysis. Estimation of rare events of first natural frequency applying subset simulation is discussed.
Stochastic dynamic stiffness of a surface footing for offshore wind turbines: Implementing a subset simulation method to estimate rare events
https://orcid.org/0000-0002-6414-5810
Abstract The purpose of this study, which concerns the stochastic dynamic stiffness of foundations for large offshore wind turbines, is to quantify uncertainties related to the first natural frequency of a turbine supported by a surface footing and to estimate the low event probabilities. Herein, a simple model of a wind turbine structure with equivalent coupled springs at the base is calibrated with the mean soil property values. A semianalytical solution, based on the Green׳s function for a layered half-space is utilized for estimation of foundation responses. Soil elastic modulus and layer depth are considered as random variables with lognormal distributions. The uncertainties are quantified, and the estimation of rare events of the first natural frequency is discussed through an advanced reliability approach based on subset simulation. This analysis represents a first step in the estimation of the safety with respect to the failure of a turbine in the fatigue limit state.
Highlights This study concerns the stochastic dynamic stiffness of foundations for large offshore wind turbines. A simple model of wind turbine structure with equivalent coupled springs at the base is utilized. The level of uncertainties is quantified through a sensitivity analysis. Estimation of rare events of first natural frequency applying subset simulation is discussed.
Stochastic dynamic stiffness of a surface footing for offshore wind turbines: Implementing a subset simulation method to estimate rare events
Vahdatirad, M.J. (author) / Andersen, L.V. (author) / Ibsen, L.B. (author) / Sørensen, J.D. (author)
Soil Dynamics and Earthquake Engineering ; 65 ; 89-101
2014-06-08
13 pages
Article (Journal)
Electronic Resource
English