It is known that bolted timber connections generally have low moment resisting capacity and poor ductility. Due to their simplicity and elegance, designers commonly use these connections to transfer shear forces and ignore the contribution of their moment carrying resistance. Although their moment capacity is ignored during design, in service these connections will likely experience bending moments not intended in the design and fail prematurely because they are governed by the tension perpendicular to grain and longitudinal shear strengths of timber: the two weakest strength properties of wood.
Preliminary work at UBC shows that self-tapping screws can be used as perpendicular to grain reinforcements for bolted glulam connections with slotted in steel plates to double their capacity while increase their ductility. This technique can also be used to retrofit damaged members to achieve significant gains in performance and reliability.
The proposed work will focus on expanding the preliminary work to develop the fundamental database for self-tapping screws needed for design code implementations so that producers and practicing engineers can take advantage of these connectors.