Numerical investigation on timber-to-timber joints and composite beams with inclined self-tapping screws

The paper presents a Finite-Element (FE) numerical investigation on timber-to-timber joints and composite beams with inclined self-tapping screws (STS). Based on past literature efforts, full 3D solid FE models were implemented in ABAQUS, for selected geometrical and mechanical configurations of composite joints of technical interest. A key role in the FE modelling approach is assigned to input material properties, including damage constitutive laws and mechanical contacts between all the model components, like surface-to-surface interactions and cohesive damage models, so as to reproduce possible local failure phenomena in the joint components. The presented FE models is then validated against push-out tests available in the literature for the examined structural typology. Comparative calculations are hence critically discussed, including numerical analytical estimations from existing models, design standards or literature research projects. Finally, the same modelling approach is applied to timber-timber composite beams, giving evidence of some preliminary FE-to-experimental observations.