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

Table 9

Basic stiffness parameters for different types of foundations.

Type of foundation	Number	N (mm)	MN·(m/rad)
The single pile foundation (d = 4 m)	1	38,464	9,257	99.1966	4.8721
The single pile foundation (d = 5 m)	2	53,936	16,064	139.0981	8.4547
The single pile foundation (d = 6 m)	3	67,955	24,244	175.2524	12.7600
The pile-bucket foundation (D = 16 m and H = 4 m)	4	52,527	10,593	135.4644	5.5753
The pile-bucket foundation (D = 16 m and H = 8 m)	5	53,888	10,731	138.9743	5.6479
The pile-bucket foundation (D = 16 m and H = 12 m)	6	54,265	10,768	139.9466	5.6674
The pile-bucket foundation (D = 20 m and H = 8 m)	7	55,048	10,786	141.9659	5.6768
The pile-bucket foundation (D = 12 m and H = 8 m)	8	52,069	10,640	134.2832	5.6000