Failure of Load-Carrying Timber Beams caused by Connections

The load carrying capacity of timber connections is whether calculated according to existing models, e.g. the so-called Johansen model for connections with dowel-type fasteners, or determined by testing, e.g. connections with plate connectors. However, when loaded perpendicular to the grain and / or in shear, cracking of the timber may limit the load carrying capacity, a failure mode with which existing models do not deal. Within CIB-W18, the last five years several papers on this subject were presented. Some of the papers discuss a possible theoretical approach based on fracture mechanical considerations; most of the papers discuss test results. At the Universities of Delft and Eindhoven in the Netherlands a comprehensive research recently started in which it is intended to develop model(s) based on theoretical considerations evaluated with old and new experimental data. Tentative first results are discussed in the paper