Taxonomic and Gross Anatomical Influences on Specific Gravity-Mechanical Property Relationships


  • David R. Walton
  • James P. Armstrong


Specific gravity-mechanical property relationship, mechanical properties


The relationship between specific gravity and modulus of elasticity, modulus of rupture, and maximum crushing strength in compression parallel to the grain was investigated for seven commercial timber genera. Exponential regressions were derived for each specific gravity-mechanical property relationship in the green and air-dried (12% moisture content) condition for each genus. The regressions were tested for significance and, if significant, compared by covariance analysis to determine if they were significantly different. The experiment was repeated, this time grouping commercial timber species according to their gross anatomical characteristics, i.e., ring porous, semi-ring porous, diffuse porous, and nonporous. Results of the covariance analyses indicate significant differences between most generic groupings and between most pore arrangement groupings. Data used in this study were obtained from the world literature.


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