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机构地区:[1]浙江林学院,临安311300 [2]延吉市林业局
出 处:《东北林业大学学报》2009年第12期18-19,34,共3页Journal of Northeast Forestry University
基 金:国家自然科学基金资助项目(30060070)
摘 要:对延吉市帽儿山坡下和坡中的人工林赤松(Pinusdensiflora)的物理力学性质差异进行研究。结果表明:坡下人工林赤松的弦向、径向和体积干缩率比坡中小;抗弯强度、抗弯弹性模量、顺纹抗拉和抗压强度、横纹弦向和径向抗压强度,坡中材高于坡下材;气干密度、弦向和径向抗剪强度、弦向和径向抗劈力,均坡下材高于坡中材;坡下和坡中人工林赤松的气干密度、径向和体积干缩率、顺纹抗压强度、横纹弦向和径向抗压强度、弦向和径向抗剪强度差异达0.01显著水平,抗弯强度、抗弯弹性模量、弦向抗劈力差异达0.05显著水平,弦向干缩率、顺纹抗拉强度、径向抗劈力无显著差异。An experiment was conducted to study the differences in physico-mechanical characteristics of Pinus densifiora wood from plantations on both lower slope and middle slope in Maoer Mountain of Yanji City. Results showed that the tangential shrinkage rate, radial shrinkage rate, and volume shrinkage rate of P. densiflora wood on the lower slope were less than those on the middle slope. The modulus of rupture (MOR), modulus of elasticity (MOE), tensile strength parallel to grain, compressive strength parallel to grain, tangential compression strength perpendicular to grain, and radial compression strength perpendicular to grain of P. densiflora wood on the middle slope were higher than those on the lower slope. The air-dry density, shearing strength in tangential face, shearing strength in radial face, tangential cleavage strength, and radical cleavage strength of P. densiflora wood on the lower slope were higher than those in the middle slope. There were extremely significant differences in air-dry density, radial shrinkage rate, volume shrinkage rate, compressive strength parallel to grain, tangential compression strength perpendicular to grain, radial compression strength perpendicular to grain, shearing strength in tangential face, and shearing strength in radial face of P. densiflora wood from plantations on both lower slope and middle slope, and significant differences in MOR, MOE, and tangential cleavage strength. No significant differences were found in tangential shrinkage rate, tensile strength parallel to grain, and radical cleavage strength.
分 类 号:S781[农业科学—木材科学与技术]
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