Modern technologies are typically compared from a pure price perspective. From a pure visual comparison, structural self-tapping wood screws may not seem to provide much benefit when compared to traditional fastening systems. However, when considering the superior strength properties inherent in structural self-tapping wood screws, major performance differences are found for withdrawal and shear capacities that make these very efficient connectors and in turn, very cost efficient connections.
Structural self-tapping fastener technology has been successfully used in Europe for the last 10 years to connect timber-to-timber elements, as well as steel-to-timber elements. The recommended design procedures presented in available product approvals for Canada and the US, follow the European Johansen Yield Model which promotes wood crushing and fastener yielding as the preferred failure modes. Utilizing threaded structural self-tapping screws in tension, rather than in shear as most traditional connection systems are employed, has opened the door to new design opportunities due to the high performance of these fasteners under withdrawal action.
This course hopes to provide a basic introduction to the presently available modern timber connection systems, as well as offering a more specific introduction to the basics of design, and performance advantages and limitations of timber connections using structural self-tapping wood screws. This course will start with the general concept of modern timber connectors, to the more specific details about self-tapping wood screws.