Effect of Reinforced Bucket on Bearing Capacity and Natural Frequency of Offshore Wind Turbines Using Pile–Bucket Foundation

Table 8

Numerical deviations of the fundamental frequency solving by different methods.

	The measured value	The predicted value by the FEM-analysis combined method	The predicted value by the finite element method	The analytical value after simplifying foundation stiffness
The first-order natural frequency (Hz)	0.369	0.359	0.328	0.342
The numerical deviation (%)	—	2.7	11.1	7.3