Bundling elastic gridshells with alignable nets. Part II: Form-finding

• Published in: Automation in construction Vol. 141; p. 104292
• Main Author: Tellier, Xavier
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2022
• Subjects: Active-bending; Architectural geometry; Elastic gridshells; Form-finding; Optimization; Active-bending; Elastic gridshells; Form-finding; Optimization; Architectural geometry
• ISSN: 0926-5805; 1872-7891
• DOI: 10.1016/j.autcon.2022.104292

This two-part article introduces the concept of alignable nets, forms of elastic gridshells which may be deployed from a compact bundle state, thus offering advantages for transportation and prefabrication. Whereas the first part focused on analytical solutions, this second tackles their numerical form-finding. A design workflow is introduced to design a bundlable gridshell with a target surface and boundaries as inputs. Contrary to most other algorithms on irregular gridshells, the method does not simulate the deployment kinematics, but rather ensures the deployability by a simple local constraint derived from equations of scissor linkages. It turns out that the design space is significantly larger than the one of regular Chebychev gridshells with constant node spacing, hence allowing to further optimize a given gridshell geometry for other constructive aspects. The method is validated on several examples, prototypes and commercialized structures. •This article studies the shapes of grids of beams that may be deployed from a bundle configuration.•A discrete model of these grids is introduced using equations from scissor linkages.•A simple form-finding method is proposed based on iterative projections. Inputs are a target surface and target boundaries.•Bundlable gridshells appear to be much less constrained geometrically than regular gridshells with constant node spacing.•This additional design freedom can be used notably to align a grid with target boundaries or to reduce permanent stresses.