Safety Evaluation of a Hybrid Substructure for Offshore Wind Turbine

Table 6

Soil conditions.

	Depth; (m)	SPT; (N)	Density; (kN/m^3)	Adhesion; (kPa)	Internal friction angle (°)
Silty sand	0.0~7.5	5/3016/30	19.0	—	27
Silty clay	7.5~10.5	4/30~12/30	18.5	44.5	—
Silty sand	10.5~24.3	24/30~50/27	19.0	—	38
Weathered soil	24.3~27.0	50/15	19.0	25	31
Weathered rock	27.0~34.0	50/7~50/3	21.0	34	32