Imagine the strength of the foundations required to withstand the forces operating on the world’s biggest wind turbine standing 245 metres above ground. And then imagine that those foundations need to be constructed in sandy, soft soil. This was the challenge facing our structural and geo-technical experts.

The Haliade-X was developed by General Electric (GE) to increase the output and efficiency of future off-shore wind farms. The turbine has an installed capacity of 12MW and rotor diameter of 220 metres. While the turbine is destined for off-shore purposes, its test-site is on-shore for easier access and is located in the Netherlands on reclaimed land, created with dredged material.

Models avoid over-dimensioning

Royal HaskoningDHV has a dedicated team of structural and geotechnical experts with many years of experience with on-shore wind farms. We work for and with many major stakeholders in the wind industry and therefore understand the needs and worries of developers, suppliers, contractors and insurance companies.

The models we have developed over the years allow us to explore options and deliver the optimal foundation design, including a full 3D model of the reinforcement where we pinpoint and solve clashes at an early stage. Recognising that cost is a very important driver, we identify the optimal foundations with such precision that over-dimensioning is avoided.

Our finished design for the Haliade-X foundations meets the technical requirements and involves a 28-metre concrete slab which is supported by 48 round piles.