What was the customer’s request?

The execution of new foundations by means of micro piles for the phased renovation and extension of the substation at Merksem.

What technical challenges did the project pose?

The micro piles serve as foundations for the extension to the relay building, lighting columns and lightning conductors.

As the piles are installed at intervals between and around the existing installations, restricted accessibility had to be taken into account. In addition, there was limited free working height since the high-voltage installations remained in service.

The micro piles have to absorb not only tensile and compressive stresses, but also a horizontal load. For this reason, the original design was made with tubular piles.

How did CVR tackle it?

The materials used (anchor rods, steel pipes etc.) have a limited length. We have fitted our anchor drilling machine with a short drilling mast and the necessary sensors and safety devices so that we do not exceed the height restriction.

The horizontal load is absorbed in two ways. In the case of groups of piles (three or more piles), the micro piles are drilled obliquely with respect to each other so that they absorb the load together. The stand-alone micro piles are fitted on top with a steel pipe, because the central rod of the micro piles cannot absorb the horizontal load alone. With the steel pipe as additional reinforcement, all loads can be transferred to the subsoil without any problems.

What was the end result?

Thanks to the extensive research and computations with detailed procedures, we were able to have our alternative proposal with micro piles instead of tubular piles approved. Thanks to our practical knowledge and experience, we were able to execute the activities without any issues and to the customer’s satisfaction.