LRFD FOR ENGINEERED WOOD STRUCTURES - CONNECTION BEHAVIORAL EQUATIONS

A new design specification for engineered wood structures has been pro posed in load and resistance factor design (LRFD) format. This paper p rovides an overview of the proposed LRFD connections design criteria. he connections design provisions are, in part, calibrated from allowab le stress design provisions. Major changes from historic practice, how ever, result from a change in behavioral equations to a theoretical ba se for predicting the lateral strength of connections using bolts, scr ews, and nails. New provisions for axial withdrawal of driven and turn ed fasteners, as well as combined axial and lateral loading criteria a re also proposed. Safety levels were calibrated to historic practice, but some change in design capacity is expected due to format change, c onversion to new behavioral equations, and the selection of a calibrat ion point. The LRFD document contains substantial improvement in code clarity, simplification, and structure over the historic allowable str ess specification. A clear mechanism for including design with new woo d-based engineering materials is provided.