Timber Folded Plate Structures - Folded Form Analysis

Abstract

<p>This paper analyses the potential of different possible folded form topologies for generating timber folded surface structures. The main advantage of such structures lies primarily in the realm of ecology and sustainability. By offering an integral way of construction, which fulfils both a supporting as well as a covering function, very lightweight structures are achieved. Also, a greater degree of prefabrication is possible which leads to a reduced overall cost. As these structures consist of a large number of discrete, thin plane elements, proper edgewise connection details are needed in order to ensure an efficient load bearing system. For structures made of wood products this presents a great challenge using the state-of-the art joining techniques. For this reason, the use of timber folded plate structures in civil engineering applications has been very limited. However, recently new technical solutions have been proposed for efficient edgewise joining of thin timber panels. In this paper focus is put on integrated mechanical attachment technique which utilises digital prefabrication to integrate connectors through panel geometry. Considering the material and the chosen connection detail fabrication as well as assembly related constraints, feasible folded forms for folded surface structures are explored. Their influence on structural performance is studied and different forms are compared by means of Finite Element Analysis. Furthermore, based on the obtained results, form improvements are proposed and observations made on a case study of a built prototype structure are presented.</p>

From Folds to Structures, a Review

“…An interesting illustration of this trade off is given by Ibois [117] where a generalization of Miura ori was directly built with rather thick wood plates mechanism is completely focused in the hinges (Figure 24) and shows that the wood itself is loaded below its actual strength. Improving connection strength appears as a first answer and is an active field of research [118,119,120,110]. However, the observation that thickening the folded shape focuses the deformations in the folds points out a stringent limitation to structures derived from folds: either, the structure is thin, light and cannot sustain large loads, or it fails in the folds.…”

Experimental investigation of the influence of integral mechanical attachments on structural behaviour of timber folded surface structures

“…The initial slip effect in a multiple plate assembly is com- either the left or the right side at mid length of the struc-570 ture, when the two half-sized plates edges failed in tension. 571 As explained in [12], structural behaviour of folded surface pairs of contact faces exist, ij 1,2,3,4 (Fig.17b) edge length simultaneously in a brittle manner, the soon 638 following system failure is brittle as well. So in this case, 639 it is the topology alone that provides the redistribution of 640 forces and avoidance of complete structural failure imme-641 diately after the adhesive ultimate strength is achieved.…”