Mechanical Properties In Relation To Specific Gravity In 342 Chinese Woods


  • Shu-Yin Zhang


Specific gravity, mechanical properties, wood categories, Chinese woods, regression equations, relationships


Based on 342 Chinese timber species separated into five distinct categories, relationships of various wood mechanical properties (S) with specific gravity (G) were examined at: 1) species rank; 2) generic rank; 3) the category rank as well as in all the softwoods or hardwoods as a whole. The curvilinear equation (S = αGβ) was compared with the linear one (S = a + bG) in terms of the goodness at predicting mechanical properties through specific gravity. The results indicate that the mechanical property-specific gravity relationship varies remarkably with the taxonomic rank, the wood category, and wood mechanical property. Further, the goodness of the two equations in terms of the coefficient of determination also varies appreciably with the rank, the wood category, and wood mechanical property. As a whole, however, the curvilinear equation appears to be better than the linear one at predicting most mechanical properties, particularly at species rank and in terms of the regression coefficients.


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