Improved design methods for connections perpendicular to grain

Timber elements loaded perpendicular to the grain by connections may fail as a result of exceeding either the embedment strength or the splitting strength of timber. Which failure mechanism develops depends upon parameters like the connection geometry in terms of fastener diameter and spacing, and the timber species. It is shown that accurate predictions of the load-bearing capacity can be made based upon mechanical models, which take account of such parameters. Basically, two different design equations are proposed which account for either one of the failure mechanisms. Based upon these equations, theoretical statements can be made concerning certain strength-affecting parameters, like fastener diameter, and its influence on the governing failure mechanism. For validation purposes, these models are verified with an extensive experimental data base. A proposal for design code implementation is given as well