Monopile Foundation Stiffness Estimation of an Instrumented Offshore Wind Turbine through Model Updating

Table 1

Normalised frequency bands used for selection of tower modes.

	Normalised frequency band,	Initial empirical estimate
		FA,	SS,
1^st tower	0.94–1.04	0.99	1.00
2^nd tower	3.69–4.29	4.02	4.16
3^rd tower	9.22–11.74	9.73	11.23