Long term effects of cyclic loading on suction caisson foundations in sand

Offshore wind turbine projects have been characterised by an increase in costs, sizes and distances from shore, EWEA 2012 This created a need of investigating the adequacy of alternative and more fìnancially attractive foundation types such as suction caissons. Within a multi-footing configuration, such as a three-leg jacket structure, these foundations prove to be an advantageous sotution for increasing water depths lt is due to their configuration that a simpì.ified design is possibLe, leading to onty vertical cyclic loading conditions. This article provides a concise summary of the M Sc. thesis of C. Lupea and presents an approach that may allow for the simplìfication of the long term performance assessment under vertical cyclic loading of suction caissons ennbedded in sand lt provides a conservative theoretical base for the ideniification of potentiatly damaging loads, which could cause significant pore pressure build-up and strain accumulation. One of the key conclusìons of this research is that the foundation response is a function of both the applied mean load and its cyclic amplitude for both tensile and compressive loading. Nonetheless, experimental work rnust be carried out to validate these resultsGeoscience & EngineeringCivil Engineering and Geoscience