SPF规格材密度与节子变异特性对抗弯性能的影响

The Influence of Bending Performance by the Variations in Wood Density and Knot of SPF Dimension Lumber

探讨了密度、节子对SPF规格材弹性模量和静曲强度的影响。考虑到材料在不同构件中受力方式不同,试验采取了平弯和侧弯2组。结果表明,节子的大小和数量是影响材料抗弯性能的重要因素。在密度相差不大的情况下,木节相对尺寸的大小与抗弯强度成反比;密度与弹性模量及静曲强度存在一定的线性关系。

The study was to evaluate the effects of density and knot on the modulus of elasticity（MOE） and modulus of rupture（MOR） of SPF dimension lumber.Considering about the different stress modes in different structures,the flat and lateral bending was adopted in the experiment.The results show that the number and size of knot are the main influencing factors on the bending performance.When the densities are similar,the relative size of knot is inversely proportional to the bending performance.The density has certain quantitative relation with MOE and MOR.