Soil uncertainty propagation for offshore wind turbine monopile design

Foundations contribute to around 30% of offshore wind capital expenditure. Due to significant uncertainties in soil properties, it is important for wind farm development to evaluate the propagation of those uncertainties through various design criteria. In the early design stages, data availability is scarce. As the project advances, geotechnical campaigns are performed, increasing the ground knowledge and reducing the overall uncertainty. The objective of this article is to provide a methodology to quantify the impact of uncertain soil properties on geotechnical design criteria for offshore monopile foundations. The approach proposed in this article is based on metamodels, allowing identification of predominant soil parameters and possible correlations between soil properties inputs and foundation outputs. The geotechnical criterion used in this paper is the critical pile length.