Splitting of timber beams loaded perpendicular to grain by connections – Combined effect of edge and end distance

The paper presents experimental results of tests on splitting of laminated veneer lumber beams subjected to loading perpendicular to grain by single bolts with small edge and end distances. Two different edge distances were used, and a total of eight different combinations of edge and end distances were tested. Material properties such as perpendicular-to-grain tensile strength and mode I fracture energy of the tested beams were also determined by testing. The experimental results are compared with a simple analytical model based on quasi-nonlinear fracture mechanics, which takes into account the effect of the edge distance as well as the end distance. A generalized model is proposed, which applies to small and large edge distances and to small and large end distances, and which contains as a special case the linear elastic fracture mechanics model, which is currently used as the basis for calculation of the splitting capacity in the Europeans and Canadian timber design codes.

► We consider splitting of timber beams loaded by a bolt near the edge and near the end.
► We propose a generalized quasi-nonlinear fracture mechanics model.
► We validate the model by testing.
► We point out some problems with existing models and design codes.