Effects of Wood Decay By <i>Postia Placenta</i> on the Lateral Capacity of Nailed Oriented Strandboard Sheathing and Douglas-Fir Framing Members

Authors

  • Scott M. Kent
  • Robert J. Leichti
  • David V. Rosowsky
  • Jeffrey J. Morrell

Keywords:

Wood decay, brown rot, <i>Postia placenta</i>, connections, yield models, OSB (oriented strandboard), nails

Abstract

The effect of wood decay on the single shear strength of nailed oriented strandboard (OSB) sheathing to Douglas-fir framing member connections was investigated. The connections evaluated in this study were representative of those present in lateral force resisting system components of light-framed wood structures, including shear walls and horizontal diaphragms. Strength and stiffness of the nailed connections were characterized using monotonic testing of samples exposed for increasing intervals to the brown rot fungus, Postia placenta. After the destructive tests, portions of the sheathing and framing member from the samples were further evaluated for dowel bearing strength and weight loss. The results indicated that existing yield models used for design of nailed connections can predict nominal design values for nailed connections of OSB sheathing and Douglas-fir framing members with various levels of decay damage, provided that the dowel bearing capacity of the wood materials can be assessed.

References

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Published

2007-06-05

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Section

Research Contributions