Effect of Climate Change on the Reliability of Offshore Wind Turbine Foundations

Abstract

The reliability of monopile supported offshore wind turbine (OWT) is assessed considering the uncertainties in aerodynamic and hydrodynamic loads and spatial variability of soil. Traditional designs assume that applied loads are constant during the design period of OWTs. However, fluctuations in climatic conditions alter the future wind and wave loads because of which time-dependent reliability assessment of OWTs is performed in this study. Statistical downscaling method using the general circulation model corresponding to the A2 emission scenario is used to predict the future wind and wave responses. The impact of climate change on the probability of failure for the serviceability limit state of maximum allowable mudline rotation is studied. The uncertainties in soil properties, and wind and wave loads are incorporated in the analysis. The reliability of an OWT structure founded in sand is investigated for the period 2015-2050. The OWT system is modeled using a beam supported laterally by a nonlinear Winkler foundation characterized by the American Petroleum Institute recommended cyclic p-y curve for sand. This study shows that the reliability of OWT is changed significantly because of the effects of climate change. � ASCE.