DOUBLE SHEAR TIMBER CONNECTIONS WITH DOWEL TYPE FASTENERS

For the design of single fastener connections with dowel type fasteners Johansen's Yield Model extended by Meyer is generally adopted. However, since this model gives a poor prediction of the load carrying capacity of single fastener connections with rigid fasteners, an extension based on fracture mechanics considerations was developed. The strength of multiple fastener connections does not equal the strength of the single fastener connection multiplied by the number of fasteners. Generally the connection fails at a lower load because the timber splits and/or because of softening of the wood, which can be explained by the complicated stress distribution around the fastener position. The stiffness of multiple bolted connections is lower than the stiffness of the single bolted connection multiplied by the number of bolts, which can be explained by the individual hole clearance. Both the strength and stiffness of multiple fastener connections and the strength of single fastener connections with dowel type fasteners were studied.