Simplified Calculation Method for the Natural Frequencies of the Offshore Wind Turbine Structures with Monopile Foundations Based on Euler–Bernoulli Beam Theory

Table 5

Comparison of natural frequencies calculated using various methods.

Method	Natural frequency without SSI (Hz)	Deviation (%)	Natural frequency with SSI (Hz)	Deviation (%)	Deviation (%)
Ko [38]	0.228	−0.885	0.2271	−13.041	0.395
Yang [40]	0.192	15.044	0.1874	6.720	2.396
Arany et al. [10]	0.206	8.850	0.1981	1.394	3.835
Method herein	0.221	2.212	0.2176	−8.313	1.538
Alkhoury et al. [42]	0.226	–	0.2009	–	11.106