Optimal design of gridshells.

Gridshells are shells composed of wood, composite, or steel bars. During the past decades, gridshells have gained a lot of popularity as a structural system to cover large spans. Examples are the Multihalle in Mannheim and the roof structure of the Maritime Museum in Amsterdam. Traditionally, gridshells are designed using formfinding methods. These methods are based on the simulation of physical models such as the hanging chain models used by Frei Otto. They have the advantage that they provide the designer with a large degree of control over the shape of the gridshell. Alternatively, numerical optimization techniques can be used. These techniques are capable to find the most material efficient design, but they do generally not allow for much input from the designer. Combined methods have also been proposed, where the shape of the shell is determined first by means of formfinding, and the layout of the lattice is determined afterwards using numerical optimization. The aim of the proposed project is to develop a novel method where formfinding and numerical optimization are used simultaneously. This approach will unite the advantages of formfinding (to account for designer preferences) and numerical optimization (to find the most efficient design within these constraints). In order to obtain a realistic design, complex phenomena such as geometric imperfections and buckling will be modeled, and the relevant practical constraints will be taken into account.