Finite element simulation of mechanical and moisture-related stresses in laterally loaded multi-dowel timber connections

Numerical simulations of stress distribution within a moment stiff timber frame corner have been performed. The frame corner is a multi-dowel connection with two slotted-in steel plates. The interaction between the fasteners and the wood material is modelled as a full contact interaction based on penalty formulation. The wood material is assumed to be an orthotropic material in reference to elastic and shrinkage behaviours. Both mechanical loading (from snow and wind) and moisture loading have been studied. Model adaptivity was used to reduce the computer time and to find suitable coupling conditions between beam and solid elements. The simulation results have been compared with typical hand calculations. The conclusion is that the hand calculations diverge quite a lot from the simulation results and relatively small moisture changes can cause significant stresses in areas adjoining the fasteners.