JOINTS IN TIMBER STRUCTURES LOADED PERPENDICULAR TO GRAIN – COMPARISON OF DESIGN APPROACHES QUERANSCHLÜSSE IM HOLZBAU – EIN VERGLEICH VON BEMES- SUNGSANSÄTZEN ASSEMBLAGES DES STRUCTURES EN BOIS CHARGEES PERPENDI-

The paper reports on the design of joints in timber beams loaded perpen-dicular to grain. Such joints are highly prone to splitting and in most cases the load-carrying capacity of the joint depends on the tension resistance perpendicu-lar to grain rather than on the lateral load capacity of the dowel type fastener. The models developed for design of such joints with respect to failure in tension perpendicular to grain can be grouped in strength of materials approaches and linear fracture mechanics models. A design based on tension strength perpen-dicular to grain is implemented in the new version of DIN 1052:2004 being very close to the quasi-standardised design procedure in the frame of the still valid “old ” German timber design code based on permissible stresses. Contrary, Euro-code 5 contains a fracture mechanics based model. In the paper presented, a specific joint type with a single dowel-fixed steel plate in a glulam beam is considered and the design capacities according to the different code rules are evaluated. As parameters, the numbers and rows of fas-teners are varied. Configurations with large effective joint heights, i.e. with