Uncertainties in the response of tower-like structures to wind gust buffeting

The optimization of the installation process of offshore wind farms passes through a detailed planning of the activities with careful evaluation of the risks and consequences of a failure. An accurate assessment of the frequency or probability of a structural failure is a crucial input of such an optimization. A case study dealing with the reliability of the temporary foundations used for assembling wind turbine towers at the quayside, before being loaded onto the installation vessel, is presented. The statistical uncertainty embedded in typical calculation for assessing the response of a tower-like structures to wind gust buffeting is discussed. Besides, the role of statistical and epistemic uncertainty affecting other parameters involved in the load calculation is investigated, namely the maximum wind speed, the structural damping estimated through full scale measurements and the aerodynamic coefficients estimated through wind tunnel tests.