The new face of the Stedelijk Museum is becoming more noticeable by the day. A large part of the panels are already in place on what will eventually become known as "The Bathtub." After coating, the white and seemingly floating construction, with its sleek finish and without any seams or details, will be the counterpart of the adjacent historic brick building from 1895. The Japanese fiber manufacturer Teijin produced and donated the Twaron (aramid fiber) and Tenax (carbon fiber) for the composite used to create the facade.
The facade, designed by Benthem Crouwel Architects, consists of a single surface and covers an area of about 3000 square meters, which is smooth and gleams in the sun. A solution was required that would minimize thermal expansion of the material in order to obtain a seamless effect. The design, development, and production of the facade required creativity and input from several experts. Ultimately, the key to the solution was found in the Twaron and Tenax fibers.
An analysis provided by the engineering firm Solico showed that an optimal solution would consist of a sandwich construction. The construction consists of an inner skin and outer skin of a composite laminate of resin, strengthened by Twaron and Tenax fibers. Where the resin expands as the temperature rises, both Twaron and Tenax fibers, due to their negative longitudinal thermal expansion coefficient, behave oppositely. The result is a composite panel with minimal thermal expansion.
The composite for the seamless facade of 100 meters expands by only 1 mm per degree Celsius temperature rise. The same facade based on a fiberglass composite or aluminum would expand almost two and a half times as much.
Production of the Panels
For the production of the panels, Teijin provided Twaron and Tenax fibers to Holland Composites. A unidirectional fabric was produced from the fibers as an intermediate product.
Holland Composites produced the panels for the facade from the fabrics, vinylester resin and a PIR foam core. The inner skin and outer skin of the sandwich construction consist of two Twaron fabrics with a Tenax fabric in between. The fibers are perpendicularly oriented to each other.
In all, the facade consists of 271 loose elements containing 4850 kg of Twaron and 4050 kg of Tenax. The panels are mounted on site and glued together using a connecting laminate in order for the facade to form a single unit.