Gravity Based Foundations
The Gravity Based Foundation is a concrete conical / cylindrical structure of some 45m in height. This massive structure was built onshore, at the “Halve Maan” site in Ostend, and transported semi-submerged to the offshore site, where it was put on the seabed. An “empty” GBF weighs some 3000 tons. Once installed on the seabed, it was filled with sand; its total mass is 6000 tons.
SPECIFICATIONS GBF
| GBF height | 38,5 m to 45 m |
| GBF weight | 2800 tonnes to 3000 tonnes |
| Material | +/- 1060 m3 concrete + 255 tonnes reinforcement |
| Diameter base slab | 23,5 m |
| Thickness concrete wall | 0,5 m |
Jacket foundations
The jacket foundation is a steel quatropod structure grouted to and supported by 4 pin piles. The pin piles (+-2 m in diameter) are up to 50 m long and driven into the seabed. A transition piece is welded on top of the jacket, providing an access platform with 2 cranes and a cylindrical “barrel” to support the tower of the turbines.
SPECIFICATIONS JACKET
| Jacket height | 37,7 m - 47,8 m |
| Jacket weight | +/- 500 tonnes |
| Jacket OTS weight | 800 tonnes |
| Jacket Material | Steel |
