Form-finding methods for structural frameworks: a review

In structural engineering frameworks represent a huge variety of structural systems, from trusses to cable-nets, tensegrity, etc. Moreover many other structural systems, such as membranes or rigid- foldable origami can be associated to equivalent frameworks. A wide range of methods is shown in the literature, which have been conceived in order to optimize the behavior and the geometry of frameworks. The present paper proposes a review of already known optimization and form-finding techniques concerning this field, particularly focusing on the most recent developments. All the methods are discussed using a unified symbolism. Specific features of each method are pointed out; advantages and disadvantages are also discussed comparing similar approaches. Since many of the proposed methods pursue partially overlapping goals while others are just extensions of previously developed techniques, the last Section of the paper attempts to summarize common or compatible features among the presented methods.