Short-Term Creep as Related To Microfibril Angle


  • M. Lotfy
  • M. El-osta
  • R. W. Wellwood


Relationship between creep response and microfibril angle within the S2 layer of some coniferous wood tissues was examined. Constant loads corresponding to predetermined initial strain levels of 3,000 μinches/inch (A) and 6,000 μinches/inch (B) were applied to small wood strips. Microfibril angle was measured by the mercury impregnation method.

A positive linear relationship was found between microfibril angle and total creep (r = 0.82 and 0.83 for samples tested at constant loads corresponding to strain levels (A) and (B), respectively). A phenomenological approach is presented to explain the role of microfibril angle of the S2 layer in controlling creep response. Total creep was also found to be positively correlated with magnitude of applied load corresponding to a given deformation.


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