Methodology for developing a response-based correction factor (alpha-factor) for allowable sea state assessment of marine operations considering weather forecast uncertainty

The concept of the alpha-factor, a correction factor on significant wave height limit, was developed by DNV to consider effect weather forecast uncertainty in planning and executing marine operations. In this paper, new defined response-based factor, called alpha-factor α R , is proposed account for both H s peak period T p quantify their dynamic response offshore structures. A general methodology developing use assessing allowable sea states operations presented, with emphasis considering uncertainty. It consists quantification state forecast, statistical analysis responses coupled system assessment using criteria. Based methodology, an operation can be derived, terms ratio between characteristic values operational limiting parameter condition or without Then, assessed lead time, include decision-making. workable windows finally identified selected through comparison forecasts execution phase. Followed detailed description case study dealing single blade installation wind turbine semi-submersible crane vessel conducted. tip motion regarded as illustrate based frequency-domain approach. generated two machine learning-based forecasting methods considered paper. Results show that addition also requires addressed floating structures (such vessel). method provides efficient way incorporate into obtained provide good reference decision-making • address structures’ responses. regarding proposed. Allowable sates turbines investigated. will over-estimated if not included.