On the Fractional Stress Relaxation of Coniferous Wood Tissues


  • E. Kirbach
  • Lars Bach
  • R. W. Wellwood
  • J. W. Wilson


<i>Picea sitchensis</i>, <i>Pseudotsuga menziesii</i>, <i>Abies balsamea</i>, earlywood, latewood, growth increments, specific gravity, tensile tests, compression tests, rheology, moisture content


The intra-incremental stress relaxation behavior of Sitka spruce, Douglas-fir, and balsam fir was studied in tension parallel-to-grain and compression perpendicular-to-grain. The stress relaxation behavior at sustained constant deformation was found to be strongly dependent on location from which the test samples were cut and on the mode and rate of loading.


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