Geometrical description and Structural analysis of a Modular Timber Structure

The ambitious goal of the ongoing research at IBOIS, the Laboratory of timber constructions at the Ecole Polytechnique Fédérale de Lausanne (EPFL) is to develop a next generation of timber constructions made out of innovative timber-derived products, through applying textile principles on a building scale. The presented structure is a modular composition of timber folded panels, notably demonstrates an example of applying the geometric techniques used to produce modular patterns and lattices to timber construction context. This paper is dedicated to bring out the concept, to examine its fundamental mechanical properties and to improve the structural system. The geometrical modularity of the structure is investigated. The basic module is consisted of two mutually supporting timber folded panels which are slipped in, consecutively, along their cuts, to build up an arc. The inter-module connection’s stability is provided by contact boundary condition over the slide joints. Two main modeling approaches and relative geometric developments are described. The structural performance is examined using Finite Element Method and considering the non-linear contact boundary condition. The static behavior is studied under the self-weight load case as well as the modal dynamic response. According to analysis results, structural and geometrical alternatives are proposed to improve the structural performance. A prototype based on this geometric principal has been fabricated and assembled to explore feasibility of the concept in building scale.