Fatigue analysis of gravity-based foundation supporting a 10 MW OWT considering small-strain stiffness of soils

Resumo

In the past few years, gravity-based foundations (GBF) proved to be an advantageous solution for
supporting offshore wind turbines (OWT) when soil conditions represent a hindrance to deep foundations as
monopiles. In this type of support structure, soil-structure interaction (SSI) interferes directly in system stiffness.
The available standard formulations are still based on the Theory of Elasticity and do not contemplate some soil
properties, as its hardening effects when subjected to plastification. This paper aimed to investigate the influence
of an elasto-plastic soil model such as HSS (Hardening Soil with Small-Strain Stiffness) in a coupled fatigue
analysis of concrete, a critical point of GBF structural design, considering a 10 MW OWT. The results of the
proposed analysis showed low influence of small-strain stiffness, but a significant role of plasticity and hardening
effects.