Anchor Cage Design

The Bolt Cage Design

Drawing of a L-flange in an anchor cage
Drawing of a L-flange in an anchor cage
Coöperatie Zuidenwind has poured the concrete for the foundation in Heibloem in the Netherlands and created the basis for the installation of their wind turbines. The foundation design and calculation for this project was done by CTE Wind Civil Engineering. The expert in foundation design WTG suggested their Soft-Spot® instead of a typical pile foundation.
Coöperatie Zuidenwind has poured the concrete for the foundation in Heibloem in the Netherlands and created the basis for the installation of their wind turbines. The foundation design and calculation for this project was done by CTE Wind Civil Engineering. The expert in foundation design WTG suggested their Soft-Spot® instead of a typical pile foundation.
H4a Windenergie B.V. / Coöperatie Zuidenwind

The anchor cage design solution allows to optimize the foundation design and so the bill of concrete and steel quantities.

In the US a mandatory service from the structural engineer, in Europe delivered by the OEM: the anchor cage design. A well-designed anchor cage, or bolt cage, optimizes the bill of quantities of a wind turbine foundation (WTG) foundation. This special knowhow – or in French «savoir-faire» – of inhouse cage design leads CTE Wind to sophisticated foundation solutions such as the rock adaptor or the high plinth. The last mentioned helps to reach higher hub heights thanks his high pedestal. The tower stands 3 to 6 meters above the «ground level». The solution ideally provides also the design of the anchor cage. CTE Wind’s engineering team develops the cage and determines the bolt length, the pre-stress loads, the steel quality and all other necessary parameters.

The
“Von Mises” stress distribution i n a tower base flange connection to the anchor cage

Finite element method

CTE Wind uses for the design of anchor cages the finite element method (FEM) which allows to analyze the behavior of structures with complex geometries and strong loads. The picture above shows the stress distribution in a tower base flange connection to the cage. Models like that help to verify structural integrity. FEM in combination with CTE Winds «savoir-faire», allows – in case something goes wrong during construction phase – to find repair solutions. Several clients have saved money and time thanks to CTE Wind’s pathology experience and FEM-skills.

Please contact us if you are interested in knowing more about CTE Wind’s anchor cage design.