Full – Scale Evaluation of Creep Performance of Glued Solid Timber Beams for Sustainable Construction

Abstract

reducing reliance on large, old-growth timbers and other heavy materials. While numerous studies have focused on glued laminated timber beams (GLT), this research explores the potential of an innovative engineered product Glued Solid Timber (GST) beams as a durable, long-lasting alternative with broad application. This study presents a first series of experimental and numerical investigations conducted within the framework of Eurocode 5. The models (beam samples) are full-scale and are produced from Spruce (Picea Abies) in accurate dimensions in the cross section 138mm x 170mm (EN 14080-2013), while the length of the beams is determined by referring to the procedures of the standard EN 408:2010+A1, which in this case is 3570mm. Alongside the experiments, numerical simulations were carried out using the Finite Element Method (FEM) to model the performance of GST beams under long-term loading. The creep of timber is taken into account when we calculate the serviceability limit state, i.e. the limit state of deflections, and it mostly affects the deflection from long-term loads usually from the action of permanent loads. The testing of creep of timber is needed to determine the deformation factor k_def (which represents the coeffi cient of creep) which, according to Eurocode 5, depends on the duration of the load and from service class of the timber. What is particularly important is that in Eurocode 5 there are no defined values for k_def for glued solid timber, and hence the great importance of the test of creep of timber of glued solid timber (GST).