Effects of Decay on the Cyclic Properties of Nailed Connections

Abstract

The effect of wood decay on the fully reversed cyclic performance of nailed oriented strand board (OSB) sheathing to Douglas-fir framing member connections was investigated. The connection geometry evaluated in this study was representative of lateral force resisting systems of light-framed wood structures, including shear walls and horizontal diaphragms. Maximum loads, slip at maximum loads, yield loads, initial stiffnesses, and cumulative energy dissipation of nailed connections exposed to increasing intervals to the brown rot fungus, Postia placenta, were characterized using fully reversed cyclic loading. After the destructive connection tests, portions of the sheathing and framing member from the samples were further evaluated for specific gravity. The OSB sheathing specific gravity was the best descriptive variable for the mechanical properties measured in this study. Cumulative energy dissipation was the connection property most affected by decay damage.