Mechanical model to approximate the behaviour of dowel-type joints with expansive kits in timber structures

This work presents some advanced 3D mechanical models, developed using the finite element method, for dowel-type joints with and without expansive kits used in timber structures. Some key points in the design of the models are the correct calculation of the design load working on the joint, the approximation of the mechanical behaviour of the different materials which constitute these joints, the accurate description of the contact zone between timber and dowel and finally the mechanism proposed to model the effect of the expansive kit using the tools available in the commercial finite element program used. The results obtained from the models have shown a good agreement with a battery of empirical tests carried out to complete the work, and the comparisons between the results of the models with and without expansive kits show very interesting outcomes.