A new approach for assessing offshore piles subjected to cyclic axial loading

A new requirement of the BSH (Bundesamt fur Seeschifffahrt und Hydrographie, the regulatory authority for offshore wind farms in Germany), is the assessment of the effect of cyclic loading on the capacity of foundations supporting offshore wind turbines. There are few practical design methods until now. This paper presents a new approach for assessing offshore piles subjected to cyclic axial loading, which combines two known methods, the approach for static loading as developed by the Imperial College of London (termed ICP approach) and a load-transfer-approach as incorporated in software RATZ for cyclic loading. Results using this method are compared against tests performed for the Health & Safety Executive (HSE) in Dunkirk and very good agreement is found.