The CTE-Sandwich®

The CTE-Sandwich®

The CTE-Sandwich™ made by CTE Wind USA, Inc is an astonishing vertical reinforcement solution used for onshore wind turbine foundations.
The CTE-Sandwich® made by CTE Wind USA, Inc is an astonishing vertical reinforcement solution used for onshore wind turbine foundations.
SOFT-SPOT® in Kannus Windpark in Finland
The CTE-Sandwich® in combination with the Soft-Spot® in a wind farm in Finland

CTE Wind offers The CTE-Sandwich as an engineering and engineering design service for the custom design of wind turbine foundations. In The CTE-Sandwich® arrangement, the bottom mat reinforcement is run above the embedment ring sandwiching the entire foundation between two steel rings: the embedment ring and the tower base flange.

Engineers have approached the design of the pedestal/slab connection in a gravity base foundation differently in different parts of the world. In North America, vertical or “Omega” reinforcement bars are the commonly adopted mechanism for securing the pedestal to the base slab. However, vertical or Omega bars present construction challenges when they add to reinforcement congestion at a critical part of the foundation or clash with conduits. Reinforcement clashes are also unavoidable when these bars have to go through the bottom mat reinforcement layer, especially for an orthogonal bottom reinforcement layout.

At CTE Wind, we offer the vertical or Omega bar solution that North American contractors are familiar with. However, we also entice them with a “delicious” alternative: The CTE-Sandwich®. In this arrangement, bottom mat reinforcement is run above the embedment ring placing the sandwich goodies (the foundation slab) between two buns (the embedment ring and the tower base flange). Think of the concrete as the meat and the bottom and top reinforcement as the vegetables. Keeping the sandwich goodies between the buns should keep the sandwich together…. All one would need is a good grip!

The picture above shows in red the The CTE-Sandwich® arrangement in of a standard gravity foundation where the bottom mat reinforcement runs above the embedment ring.

The perfect combo:
The CTE-Sandwich and SOFT-SPOT(R) 

Aside from the analogy, The CTE-Sandwich® results in a positive connection between the pedestal and the base slab and practically eliminates the need for vertical or Omega bars, thereby saving on steel quantities. Construction is also more streamlined, particularly for round foundations with radial top and bottom reinforcement.  We also note great synergy between The The CTE-Sandwich® and the SOFT-SPOT® … These technologies work hand in glove to achieve the best outcomes in terms of optimizing quantities and improving constructability without compromising reliability!

Please contact us if you are interested in knowing more about The CTE-Sandwich®/SOFT-SPOT®  combo