Curved folding dome | Germany
20 maart 2023
Project: Curved folding dome, Aachen | Germany
University: TRAKO - Chair of Structures and Structural Design, Faculty of Architecture, RWTH Aachen
Design Team: Jil Schneider + Team Trako (Alex Seiter, Thorsten Pofahl, Kevin Moreno Gata, Martin Trautz)
Year of Construction: 2021
Product: ALUCOBOND® PLUS Mill finish
INSIDE OUT BOWL
Geodesic spheres are globes composed of geometric planar surfaces. This means that instead of using curved surfaces to create the sphere’s curvature, multiple flat surfaces are joined together in such a way that they form a polyoctahedron. The greater the number of faces and edges created in the process, the more spherical the body appears. But structures built in this way are complex: the curvature of the spherical surface leads to a distortion in the planar surfaces. The result is that individual segments are not identical and must be calculated individually. In spite of the complexity, a team from RWTH Aachen University dared to take on the task. It constructed a very stable geodesic sphere using only 4 mm thick ALUCOBOND® composite panels. They designed five different components, 16 of which were assembled to form a triangle, and the triangles, in turn, form the sphere. Joining the thin elements together securely is key to success. The team developed circular connecting screw plates to straddle the joints, which it countersunk in round recesses to make them flush with the surface. Because they also planned different sized openings, the dimensions, cutting and edging of the segments also varied. No problem with ALUCOBOND® because it is easy to cut and fold with extreme precision using CNC machines. It is lightweight, so the team members were able to screw the segments together themselves on the construction site. The team obviously liked the metallic sheen on the rear surface of the panels. And because the structure, unlike a real sphere, is made up of flat parts rather than curved ones, all the composite panels can be installed the wrong way around. So the sphere was built inside-out: the right side of the ALUCOBOND® panels face inward, while the aluminium reverse side, including the manufacturer's logo, is visible on the exterior. Well, in this sphere of activity, scope and leeway is an essential factor.