红锥和西南桦人工林木材力学性质的研究

为了研究树木南北向与径向位置的变化对人工林木材力学性质与气干密度的影响，该文通过对红锥、西南桦人工林木材南北向、近髓心和近树皮2个不同径向位置的力学性质以及气干密度进行测定，分析了南北向和不同径向位置2个因素对两种木材力学性质和气干密度的影响，以及木材密度与抗弯强度、抗弯弹性模量、顺纹抗压强度的相关性.结果表明:南北向的不同对红锥和西南桦人工林木材的大多数力学性质测定项目和气干密度无显著影响，仅有红锥的弦面顺纹抗剪强度、径向握钉力和西南桦3个面的表面硬度表现为南北向差异显著.近髓心和近树皮径向位置的不同对红锥的抗弯强度、抗弯弹性模量、顺纹抗压强度和气干密度无显著影响，但对西南桦的影响则全部达到差异显著水平.两个树种木材的气干密度与木材力学性质均表现为显著的正相关关系. 

Mechanical properties of Castanopsis hystrix and Betula alnoides plantation wood

In order to investigate the effect of different parts(North or South) and radial directions(Near pith or near bark) on the mechanical properties and dir-dried density of plantation wood,the mechanical properties and air-dried density of plantation-grown Castanopsis hystrix and Betula alnoides at different parts and radial directions were studied.The effect of the two factors mentioned above on the mechanical properties,air-dried density and the correlation between wood density and three main mechanical properties(bending strength,modulus of elasticity in bending,compressive strength parallel to grain of wood) were discussed and analyzed.The results show that there is no significant difference for most mechanical properties and air-dried density between the samples from north and south directions for both species.However,significant differences of shearing strength parallel to grain of tangential face,nail hold ability of radial direction,and surface hardness of three faces,between the samples from north and south directions are observed for C.hystrix and B.alnoides.There is no significant difference for the three main mechanical properties and air-dried density between the samples from near pith and near bark for C.hystrix,while the significant difference is found for B.alnoides.There is remarkably positive correlation between air-dried density and wood mechanical properties for both species.