Lateral Load Capacity of WikiHouse Composite Walls from CNC-Cut Timber

Abstract

Computer-numerical-control (CNC) fabrication of interlocking plate timber structures is a novel construction method that allows to build structural elements without mechanical fasteners: the load transfer mainly relies on direct contact and friction between the composing panels. In this work, the lateral load capacity of shear walls formed from interlocking CNC cut plywood elements is investigated for the first time by means of experimental testing. The experimental campaign comprises four full-scale 5.4×3.1 m wall specimens with and without window openings, and component tests on shear connectors and pegged connections that resist uplift at the base of the wall. A simplified analytical model is proposed and calibrated to capture the response of the wall specimens. Satisfactory agreement with the experimental results in terms of vertical and horizontal displacements can be found, but it is clear that the component tests on the holding-down pegs capture only part of the flexibility of the connection of the wall to the base, and a parameter calibrated based on the full-scale wall tests is required to represent the measured behavior. The failure load can be predicted with reasonable accuracy where failure is initiated by the hold-down connectors.