ABSTRACT
Monopiles are the most popular foundation type supporting offshore wind turbines. The use of 3DFE modelling to analyse the pile response has grown significantly in recent years, supported by the introduction of the PISA framework and the development of easy to use commercial software such as PLAXIS Monopile Designer. In sands, the small-strain hardening soil (HSS) model is widely adopted for monopile design, partially due to its relatively simple set of soil input parameters. However to date there is no widely used approach for determining the required soil parameters and approaches often differ across the industry. Igoe and Jalilvand (2020) developed an approach to derive the HSS soil model parameters directly from CPT data. This procedure has been validated by the authors for monotonic loading against a database of large-scale field tests including PISA field tests in the Dunkirk marine SAND. This paper examines the use of the 3DFE approach under cyclic loading to determine soil damping for monopiles. The results from the 3DFE analysis are compared to field test data and show a good match with the damping estimated under two-way cyclic loading.
