Review of methods to assess the structural response of offshore wind turbines subjected to ship impacts

This paper presents a literature review of analytical, numerical, and experimental methods for evaluating the structural response of Offshore Wind Turbines (OWT's) during ship collision events. The different energy transfer mechanisms involved throughout a collision against fixed or floating OWT substructures are examined, whilst documenting some of the most common procedures in the assessment of wind load effects, soil–structure interaction, mooring lines contribution and hydrodynamic coupling. A survey of internal mechanics and external dynamics approaches developed for ship-structures collision events is carried out with a discussion on their potential application in analyses involving different types of substructures. Moreover, different hydrodynamic coupling schemes found in the literature are studied, highlighting the importance of hydro-effects in the collision analysis. Common practices in the use of metallic and cementitious material constitutive models in ship-collision analysis are also presented, whereas the structural behaviour of reinforced concrete structures submitted to impact loads, which has been rarely studied outside high-velocity impact/blast applications, is discussed in the current context. Finally, some of the most important limitations of the analytical and numerical models used in ship-OWT collisions are identified, from which suggestions are provided for future research endeavors.