Adjustable formwork for fast and flexible windmill foundationsFormwork with a 15-23 metre diameter

Everywhere you look, the Netherlands is working on the energy transition. Open a newspaper or visit a news site and you cannot escape it: all of us are working together on more sustainable forms of energy. One of the results is the continued increase in the number of windmills. Hendriks precon supplies various formwork solutions for this purpose. Dura Vermeer Infra National Projects benefits from the flexibility of this formwork.

Windmills. They are popping up like mushrooms throughout the country. Speed and flexibility are of major importance in the construction of windmills. Jan Wesdijk at Dura Vermeer Materieel is well aware of this. “Our company has accepted a large number of projects. The faster the windmill is in place, the faster it starts paying for itself. Flexibility in particular plays a role in constructing foundations. After all, not all windmills are the same and the foundations consequently must comply with different requirements. The trick is to use formwork that time and again can be used to create a suitable foundation.”

Hendriks precon at an early stage realised the importance of the windmill market. This is why the company invested in acquiring expertise and experience in formwork technology for windmills. This knowledge now is of major value for contractors. “A steel formwork for windmill foundations that can be used to vary the diameter for different windmills has been developed in cooperation with Hendriks precon. The formwork can be used to construct foundations with a diameter varying from approximately 15 to 23 meters. The formwork can be used to vary the diameter in fifty centimetre increments. This way the same formwork can be used for multiple windmill projects. The height of the formwork can also be varied from approximately 1.80 m to 2.70 m.”

Separate parts

The steel formwork is assembled from separate panels that are 6 m in length. “The separate panels are easy to assemble. By using more or fewer panels and supplementing them with adapters that are 1 or 3 metres in length, the formwork’s diameter can easily be increased or decreased. And given the formwork’s variable diameter ranging from 15 to 23 metres it can be used for a large number of projects.” The round formwork is equipped with rinsing hatches and is centreless; it therefore does not require adjustable shoring. The formwork has a 6 mm thick shell plating that makes it sustainable.

In addition, Hendriks precon also supplies fixed or adjustable round formwork with a diameter that can be adjusted to between 5 and 9 m in 10-centimeter increments. Furthermore, Hendriks precon signed for parking/transport frames, platforms for safely reaching the inside of the anchor cage, as well as the insulation on the outside of the formwork and the magnetic supports for creating the bevelled edge.

When asked about the cooperation with Hendriks precon, Jan responds enthusiastically: “To put it succinctly, the cooperation is excellent. We purchased two formworks for a project in Moerdijk that required seven foundations to be poured. They perform perfectly and guarantee an excellent end-result. We can have the formwork ready for pouring in several hours. The method of working is very structured: after the work floor is poured the rebar is installed and the formwork is assembled. The concrete can then be poured. A walking platform and railings and ladders at the edge of the formwork provide the necessary safety systems. And through the smart adjustment options, we can make the Netherlands a bit greener that much faster.”