Modelling of fabric structures and associated design issues

Fabric structures demonstrate an enormous application potential of tensioned fabric as a medium for creating dramatic looking, ‘free‐form’ architectural enclosures. However, their design presents a number of challenges. Firstly, their shape cannot be known accurately at the outset; it has to be found through a process of form‐finding. Secondly, under imposed loading (wind or snow), they exhibit a visible form‐force interaction, which has to be taken into account at the load analysis stage. Finally, the manufacture of a 3‐dimensional fabric surface has to involve a patterning stage, which maps the surface onto a series of 2‐dimensional panels cut in unstrained fabric. As discussed in this paper, all of the design stages require specialist computational modelling based on good understanding of the relationship between form and stress. Much of the discussion in the paper centres on misconceptions associated with form‐finding, as well as the inadequacies of some computational approaches to form‐finding and patterning. The question of what constitutes an optimal form points to the use of natural principles in the conceptual design of fabric structures