Primary Creep in Douglas-Fir Beams of Commercial Size and Quality


  • Robert J. Hoyle
  • Michael C. Griffith
  • Rafik Y. Itani


Beams, deflection, relative creep, creep


Primary creep of nominal 4- x 4-inch Douglas-fir beams of No. 2 grade was measured at four levels of stress, at 12% wood moisture content.

Equations are presented for deflection and relative creep at the four stress levels. Results show relative creep to be nearly independent of stress level, with some evidence that relative creep shows a negative correlation with wood elastic modulus.


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