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Carpentry joints are very common in existing timber structures and they may gain attention for contemporary structures, due to their high degree of reversibility. Therefore, reliable Finite Element (FE) models for carpentry joints can contribute to assessing their capacity and provide a better insight into the parameters influencing their mechanical properties. This paper presents a FE study (using Abaqus) of timber halved-and-tabled scarf joints, together with experimental results. The FE-model considers fracture due to combined shear and tension perpendicular-to-grain by using cohesive zone modelling. Experimental tests on spruce solid timber specimens were performed to validate the model. The specimens were constructed by the use of a CNC-machine. For comparative purposes, two handmade specimens were tested, resulting in a lower load capacity. The FE results showed that initial gaps have a considerable effect on capacity. For certain assumed initial gaps, the FE-model could predict the capacity, however, it underestimated the deformation. [ABSTRACT FROM AUTHOR]

The effects of variation in humidity coupled with long-term loading give rise to dimensional changes and creep effects in wooden elements. Many wooden products such as cross-laminated timber (CLT) plates as well as many common structural details used in timber engineering are vulnerable to variations in moisture content (MC) as well as to creep effects. This paper addresses the long-term effects in the material modelling of timber by the finite element method (FEM), also considering the viscoelastic and mechanosorptive effects in wood. The model was calibrated using both relaxation tests and creep tests. The results from both long-term compression perpendicular- to-grain tests (relaxation and creep) performed on glulam (GL30c) from Norway spruce (Picea abies) with moisture control are presented in this paper. The material model considers the effect of loading and moisture changes. For realistic comparison, the pith location of each lamella was specified in the numerical analyses. Ultimately, a comparison between the numerical results and the experimental results has been provided, exhibiting an overall good estimation of timber response. [ABSTRACT FROM AUTHOR]

• Results of experiments on friction between timber lamellas are presented. • Numerical approach used to model friction tests is suitable for full-scale decks. • The influence of butt joints on stress-laminated timber decks behavior is assessed. • The influence of pre-stressing rod locations on SLT decks properties is studied. • Some design recommendations on SLT decks are given. Stress-laminated timber (SLT) decks in bridges are popular structural systems in bridge engineering. SLT decks are made from parallel timber beams placed side by side and pre-stressed together by means of steel rods. SLT decks can be in any length by just using displaced butt joints. The paper presents results from friction experiments performed in both grain and transverse direction with different levels of pre-stress. Numerical simulations of these experiments in addition to comparisons to full-scale experiments of SLT decks presented in literature verified the numerical model approach. Furthermore, several alternative SLT deck configurations with different amounts of butt joints and pre-stressing rod locations were modelled to study their influence on the structural properties of SLT decks. Finally, some recommendations on design of SLT bridge decks are given. [ABSTRACT FROM AUTHOR]