The Role of Extractives On Short-Term Creep In Compression Parallel To The Grain of Pai Wood (<i>Afzelia Africana</i> Smith)
Keywords:Extractives, cell wall, lumen, creep, deformation, deflection
AbstractThe creep behavior of extracted and unextracted blocks of Pai wood (Afzelia africana Smith) was examined in compression parallel to grain to determine the influence of both within-lumen and wall-resident extractives. It was concluded that the lumen-located extractive fractions have no significant effect on short-term creep, while the removal of wall-resident components permitted significant and accelerated creep development. However, as the cell walls of extracted wood were more reactive to moisture, the results of creep tests of this material must be interpreted with caution. It is proposed that the mechanism of influence on compressive creep is one of extractives stiffening the cell walls.
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