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按照中国国家标准研究杉木和I-214杨树木材的抗弯弹性模量、抗弯强度、顺纹抗压强度和密度,同时按照日本国家标准研究2个树种的顺纹抗剪强度。结果表明:杉木的抗弯强度、顺纹抗压强度和密度由胸高直径处向上呈波浪形增加,抗弯弹性模量则稳定降低,但不同高度间杉木的物理力学性质没有显著差异;近树皮处木材的物理力学性质高于近髓心处木材,并有极显著差异。对于I-214杨树,只有抗弯弹性模量从髓心到树皮逐渐增加,其他的物理力学性质,最小值在从髓心到树皮的过渡区,最大值在近树皮处,从髓心到树皮,杨树的物理力学性质有极显著的差异。杉木和杨树的径面顺纹抗剪强度从髓心到树皮有极显著差异,并且近树皮的高于近髓心的木材,而弦面顺纹抗剪强度从髓心到树皮没有显著差异。木材密度与力学性质有很好的线性相关关系,木材密度是一个很好的力学强度的预测手段。
According to the Chinese national standard, the flexural modulus, flexural strength, compressive strength and density along the grain of Chinese fir and I-214 poplar wood were studied, and the parallel shear strength of the two tree species was studied according to the Japanese national standard. The results show that the flexural strength, compressive strength and density of parallel grain increase from the chest height to the wavy shape, while the flexural elastic modulus decreases steadily. However, there is no significant difference in the physical and mechanical properties of Chinese fir from different height. The physical and mechanical properties of the wood in the leather are higher than those in the wood near the center of the pulp, and there is a very significant difference. For the I-214 poplar, only the modulus of flexural elasticity gradually increases from the pith center to the bark. The other physical and mechanical properties, the minimum is in the transition zone from the pith to the bark, the maximum is near the bark, Pith to bark, poplar physical and mechanical properties have very significant differences. Cunninghamia lanceolata and poplar along the grain along the grain shear strength from the pith to the bark have very significant differences, and near the bark of the wood near the center of the pith, while the string surface along the grain shear strength from the pith to the bark No significant difference. There is a good linear relationship between wood density and mechanical properties. Wood density is a good predictor of mechanical strength.