Structural analysis of origami roofing structures

Abstract

Origami is the art of folding papers into structures. Origami tessellations are a repetition of a particular module created by folding a sheet of material along a crease to produce a three-dimensional structure. Changes in geometry and in the degree of folding of a specific formation alter the mechanical properties of the Origami tessellation. The aim of this study is to assess the effect of the mechanical and geometrical properties of Origami-inspired shelters upon their structural efficiency and to determine whether Origami tosselations could be a possible alternative for roofing solution instead of the traditional methods of roofing used in the industry. A literature review was carried out to identify the different types of Origami tessellations available. The Miura-Ori pattern, which is the most developed Origami tessellation, was analysed numerically in this dissertation using Finite Element Method (FEM) software. Miura-Ori tessellations are effected by the parameters: 'a' and 'b', being the sides of the parallelogram making up the pattern; 'y' being the angle between 'a' and 'b'; '8' being the angle of deployment, the plan aspect ratio and the spanning direction of the roof structures. A total of 11 O roof configurations, constructed using steel plate parallelograms, were modelled and analysed numerically and the required plate thickness required to withstand the corresponding external loads was determined. The structural efficiency of all the different geometrical configurations was determined on the basis of their unit weight and the optimal roof structure configurations selected corresponded to those roofs exhibiting the minimum unit weight. The results of this study suggest that the most efficient Origami structures for all the plan aspect ratios considered corresponded to a 'y' value of 50°. For the plan aspect ratio of 1.25 and 1.50, the increase in the angle of deployment, '8', improves the structural efficiency of the roof structure. For a 'y' value of 50°, the structural behaviour is less dependent on two-way spanning action. A reduction in the vertical deflection of the roof structure was observed, for an increase in the angle of deployment, 'A'. The results obtained show the potential use of Miura-Ori tessellation as a viable roofing structural system, that may be efficiently employed in the construction industry.